Range Rover P38/4.0/4.6 Common Problems and Fixes

Like its predecessor, the new Range Rover has its share of mechanical and electrical peculiarities. Here we attempt to address some of the idiosyncratic problems commonly encountered, based on the personal experiences of the author as well as information gleaned from mechanics and other owners. It is hoped that passing on these experiences may make it easier for future enthusiasts to deal with them without going through the same learning curve as I had to! More complex repair operations are covered in the Repair Operations How-To section. Tricky maintenance operations are covered in the Maintenance Operations section, and all manner of Range Rover upgrades from power boosts to installation of tie-downs in the loadspace are covered in the Mechanical and Electrical Upgrades section.

Electronic Troubleshooting Manual: It is also advisable to get this manual, known as the "ETM". It is fairly essential since the shop manual (above) contains no electrical circuits. Even the massive ETM is not comprehensive as it uses a "black box" approach to many circuits, especially those contained in the many computers (ECUs) scattered throughout the vehicle. There are separate ECUs for the engine, transmission, ABS/traction control, air suspension, body, airbag system, heating and air conditioning, cruise control, etc etc etc. Most circuits are connected in some way to the body computer -- the BeCM. Fortunately the ECUs seldom fail, except for the BeCM.

The Parts Manual -- less expensive at about $40 -- is also a good buy, especially for its pictures of the way things are put together.

Computer Code Access/Testbook Equivalents: For full details on this, see the Computer Code Scan Tools Page. Briefly, to access the fault codes and other information for such systems as the air suspension, cruise control, transmission, ABS/traction control, and other non-engine systems the $30,000 dealer TestBook is now available to non-dealer buyers as a standard Land Rover part. The Land-Rover approved system is also available through Omnitec Interro as their "T4" diagnostic system. Also available from them is a stand-alone hand held T4 tester covering 99-on models. However, cheaper substitutes have become available in the $5,000-10,000 ballpark such as the Autologic Diagnosis System and the Rovacom system, both from the UK. In the US, Atlantic British sells the Autologic system -- see their website. A "Lite" version of the Rovacom is now available which covers your specific model for about $1,000-2,000. More information on the Rovacom and Autologic systems is available on our Range Rover 4.0/4.6 Parts Sources page.

OBD-II Scanner: The Range Rover 4.0/4.6 complies with the OBD-III standard and ISO-9141. OBD-II scanners are now becoming available for about $250 or less and plug into the 16 pin connector under the passenger side dash. Although it will not tell you everything the dealer's $30,000 "Testbook" does, it can give you a lot of information about the engine and transmission fault codes specified by the OBD-II standard -- for example it will tell you why that pesky "Check Engine" light has come on. The lowest cost system I have seen is a $122 OBDII Automotive Scan Tool Browser for your notebook computer is available from Alex C. Peper, 67 Scotch Pine Dr., Islandia, NY 11772, complete with OBD-II connector and cable. Actron makes a more convenient hand-held scanner that works on all American and Import OBD-II vehicles and is sold through JCWhitney.com for $159.99. They also sell low cost scanners from Auto X-ray and Equus. Danny Ledford reports that TRW has a scan tool called the Laser 2000 that is very affordable. He says it does engine management, ABS, and electronic air, and works on new OBD-II and older serial ports. The Lowest Price I have seen for a full function hand-held OBD-II scanner for the 4.0/4.6 is $129 for the Equus 3100 at partsamerica.com. This scanner works on all US and foreign vehicles.

Tools: The new Range Rover, like the Classic, is a hodge-podge of metric and SAE fasteners, so you still have to carry both types of wrenches. Since the whole vehicle is dominated by electrics, a multimeter is essential to trying to do your own diagnostics.

Ambient Temperature Sensor Faults: The sensor that purports to tell the driver and the climate control ECU what the outside temperature is, can often be erratic.

Appearance of Book Symbol on LCD Display: The climate control display shows a book symbol when certain faults occur, including a lack of Freon in the system, failed inside or outside air temperature sensors, failed heater matrix temp sensor (see below) and failed blend motors. Not all of these conditions cause the BeCM to register a fault condition (eg if the system is discharged there is no electrical problem and the BeCM will not register it).

3-Way Pressure Switch Failure: Although the climate control system on the 4.0 is a very considerable improvement over the Classic air conditioning setup, it is not immune from failure. Mine exhibited a mysterious problem that only exhibited itself during very hot weather, making it difficult for the dealer to diagnose. When the air conditioning failed during a summer off-pavement expedition in the Nevada desert, I found a shady spot and used a multimeter and the Electrical Troubleshooting Manual (ETM) to trace the fault. It was clear that the compressor clutch was not engaging, so it was relatively straightforward to narrow down the cause of the absence of voltage here. the ECU tells the compressor to switch on or off based on various sensor inputs, so the logical first step was to see if the system's "brain" was working as designed.

One good feature of the ETM is its location information and photographs for every component and connector, making it easy to find the parts of interest. Removing the plastic cover from the kick panel on the passenger side gave access to the appropriate connector, and voltage measurements showed that the A/C ECU was indeed telling the compressor clutch to switch on. However the signal then had to get through a 3-way pressure switch, designed to turn off the compressor in the case of too much or too little pressure in the system. Clearly, the signal was not making it past this switch. Jiggling the switch connector had no effect, so there was nothing for it but to suffer through the heat for the rest of the trip! Back at the dealer (and moderate San Francisco Bay Area temperatures), nothing could be found wrong with the A/C system, but I requested replacement of the 3-way pressure switch anyway. Sure enough, this cured the problem for subsequent high temperature desert expeditions.

Blend Motor Failure: This problem illuminates the book symbol on the LCD display as soon as you turn on the ignition. Andy Cunningham has heard that turning the ignition on and off rapidly can sometimes clear this problem. If not, see the HEVAC Blend Motor Diagnosis and Replacement Page.

Compressor Clutch Failure:Another common A/C problem is insufficient voltage to the magnetic compressor clutch; as the disk and pulley gap increases with wear the available magnetic flux has to bridge a larger gap. There is an official Land Rover fix for this in the shape of an additional wiring harness which dedicates a new circuit, with its own relay (relay #10 in the engine fusebox), to the magnetic clutch. A quick fix short of this official repair was devised by Andrew Parker. He found you can remove the shim washer from behind the disk and flexure plate (see picture at right by Ron Beckett) to reduce the gap. The shim washer fits to the centre boss of the plate. I have heard from several people who have had good success with this technique.

Information Display Failure: The LCD display can appear to fail, causing fear in the owner's heart that the whole HEVAC system has gone bye-bye. Usually, this is not the case -- the LCD panel is lit from behind by a simple incandescent bulb that probably needs replacing. For illustrated details of this operation, see the LCD Backlight Repair page.

Fluid in the Footwell: If you experience water leaking into the footwell on the passenger side (ie the left side on RHD models and right side on LHD models), the cause may be a blocked or damaged drain from the air conditioning evaporator. See the Water in the Footwell section below. If the fluid is in the right hand footwell on either LHD or RHD models, and appears to be not just water but rather coolant, it is probably leaking from the heater core O-rings. See the Heater Core O-Ring Repair Page for shortcuts to curing this problem.

Heater Matrix Temp Sensor: Lonn Howard reported an intermittent HVAC problem that turned out to be caused by this sensor. After the air-conditioner had been on AUTO (or a manual setting other than LO) for a while the system would suddenly put full-hot air to the windscreen vents and the Testbook symbol would appear. By manually dropping the temp setting to LO on both sides it was possible to over-ride the fault and get the A/C back on. The Testbook revealed a bad temp sensor on the hot-coolant input pipe of the heater matrix. By pulling the cover under the glove box (or steering column if RHD) it is possible to snake your hand up to release the sensor and disconnect it from the wiring. Lonn used heatsink compound when installing the new one to ensure good heat transfer to the sensor.

Air Intake Filter: There is a long piece of foam filter under the panel in front of the windscreen, and after a while it decays and gets pushed out of position by the air flow. FItting a new one is not too difficult, but Robert Watson found a cheaper solution. He reports "I have just used black pond filter foam to replace the rotted foam HVAC external filter in the plastic plenum cover below the windscreen. Lots of different filter material could be employed and presumably keeping this effective will reduce the load on the pollen filters".

Diagnosis: The Electrical Troubleshooting Manual (ETM) is a must in my view when attempting to diagnose faults in the air conditioning or the rest of the climate control system. However, David Sparkes has a fine article entitled 'New RR - Climate Control Manual Test' at this link.

The 4.0/4.6 air suspension is an improved version of that pioneered on late model Classics. Fortunately, the software seems to be much more robust and reluctant to resort to "limp home mode" (ie lowering the vehicle to the bump stops) at the slightest fault than the Classic version was. For full details of diagnosis and repair, see our Air Suspension Operation, Symptoms. Diagnosis, Field Retrieval and Repair pages. The information below is just a brief summary of the main points.

Normal Operation which Might Seem Faulty: The air suspension is controlled by an ECU under the drivers seat, which operates a solenoid valve block in the engine compartment. The ECU has a fairly low IQ, and wastes a lot of air by raising and lowering each corner constantly trying to level the vehicle. So the system's compressor turns on frequently. Another cause of its frequent running is the fact that the pressure switch is located remotely from the air tank so the pressure drop in the thin air line makes it think more air is needed. Another annoying feature that is said to be normal happens whenever the vehicle is parked on anything but a perfectly flat surface. The system tries to level itself by lowering all springs to the height of the lowest one, then realizes it is still not level so it lowers the first spring as well and starts the whole cycle over again until the vehicle ends up on the bump stops. This rather unintelligent strategy is particularly annoying off pavement, since the ground is nearly always uneven. So don't park where there is a big rock or other obstacle under the vehicle! If you want to stop in such a spot temporarily, either leave the engine running, or inhibit the system's unintelligent operation by leaving a door or the tailgate open. Pressing the manual inhibit switch on the dash also helps reduce or ewliminate this behaviour. Finally, whether on or off road, the ECU often lets so much air out of the system overnight that when you come out in the morning it can take several minutes for the suspension to raise itself up again to normal height. This is not supposed to happen but often does, even though the suspension checks out normally on the dealer's diagnostic apparatus.

Air Compressor Vibration: After a while the air suspension compressor can get rather noisy due to the rubber mounts wearing out. A Service Bulletin (TEC600695, July 1995, "Electronic Air Suspension Compressor Noisy") recommends updating the compressor mounts with 2 STC 828 Rubber Mounts and 6 STC 3086 snubbing washers. The rubber mounts are of s slightly different design and prevent the compressor sagging to hit against the hard mounting surface. I had this done on my 4.0 and it did quieten down the compressor. Some years later after replacing my original compressor with a used one, I noticed it did not have the new style bushings and was much noisier. So I swapped the bushings over and it quietened right down. Loosened mounting nuts or overtorquing can also lead to noise.

Air Springs: The rubber air springs do wear out faster than the old coil springs. One symptom is the boot popping out of position, especially in cold weather; I had this happen on leaving the car outside in the desert overnight, in access mode, and the suspension took a good 10 minutes to return to normal height on startup in the morning. The rubber boot seems to mate with the top metal part of the spring somewhat like a tire bead, and will usually reseat itself after a while. Michael Azzariti pressure tested an old air spring he replaced on his 95 LWB (see replacement procedure); he pumped 20psi into it and put it into a bucket of water. Air seeped out from the top, between the metal and rubber joint. He tried a higher pressure and it sealed up.

Another problem is plain old cracks and holes developing in the rubber when it gets worn. This happened on one of my rear springs around 60,000 miles. It developed a leak large enough that I could hear the air hissing out when parked in low profile. Since the spring had to be ordered from the UK, I had to drive it around like this for a couple of weeks. I was impressed that the system put up with this situation without shutting down and reverting to the "get you home" mode on the bumpstops.

On another occasion one of my air springs got cut by a twig or other sharp object and burst (a loud gunshot-like sound) while on a 4WD trail, 400 miles from home. In this situation if repair parts are not carried in the vehicle, there is little choice but to drive on the bumpstops home or to the nearest dealer. With luck only the end of the car that has the fault will be on the bumpstops, and the other will stay elevated. In any case, the advice in the owners manual about not exceeeding 35 mph is no doubt put there to protect Land Rover from warranty or liability claims -- on good smooth highways and freeways I have been able to keep up with the traffic flow quite well.

Bump Stops: Make sure your bump stops are present and in good condition; if one is missing and the axle articulates fully, the range of the height sensors could be exceeded, damaging the sensor or generating a fault code.

Disabling the Air Suspension: For many repair operations you don't want the suspension to be adjusting itself up and down while you work on the vehicle. Leaving the tailgate open pretty effectively freezes the suspension, but for an extra measure of safety you can unplug the air suspension delay timer, a small black box that looks like a large relay under the drivers seat.

Fixing Faults in the Field: Full details of how to recover from EAS disasters in the field are provided on the EAS Field Recovery page. The following is a brief summary only.

A hose repair kit is available from Land Rover to fix leaks in the air lines, eg when they are melted due to exhaust heat -- see the section on fixing air line leaks.

A spare rubber bladder can now be purchased from Arnott Industries or Airbag Man for about $89, enabling field repair of air springs should they burst. Or, complete spare air springs can be carried (one for the front and one for the rear). If these or other fixable faults develop (as they have on my 4.0) when you are a LONG way from a dealer, you have two choices. If you think you can fix it, do so ASAP before the EAS ECU figures out the problem and goes into the "hard fault" mode (EAS Fault message on the message center, EAS warning light on, and all EAS lights lit up on the height control). Once it does this, even if you fix the cause of the fault you cannot reset the ECU without a Testbook or equivalent on 1995-98 models. (Don't ask me how I know this!). On 1999-2002 models with the Bosch electronics, you MIGHT be able to reset it by disconnecting the battery for a while as the memory in the main engine ECU is volatile, but I am not sure if this applies to the EAS ECU.

Alert reader Ron Beckett has recently discovered that even though the ECU is in "Fault" mode, you can sometimes restore normal suspension operation (but not clear the fault code) if you can pump up the air tank to normal pressure again. Details are provided at this link.

If you are in an awkward spot not suitable for repair work and want to delay the computer detecting the fault, crack open a door or tailgate as you drive along, remove the air suspension delay/timer relay from under the left front seat, or remove Fuse 17 from the BeCM fuse box -- any of these actions should freeze up the EAS and put it into a state of suspended animation til you get to a suitable place to do your repairs. If you open the tailgate, also open your windows to prevent asphyxiation.

If the problem is not fixable in the field, accept your fate, and let the computer go into fault mode. It will (best case) freeze up the suspension or (worst case) lower one or both ends of the vehicle to the bump stops. You can then drive merrily home or to the nearest dealer. The advice in the owners manual about not exceeding 35 mph under these conditions is doubtlessly put there to protect Land Rover from warranty or liability claims -- the ride on the bump stops is a bit bumpy but on good smooth highways and freeways I have been able to keep up with the traffic flow quite well.

Height Sensors: These are simple potentiometers (variable resistors). The front height sensors used on early 4.0/4.6 models can sometimes be knocked out of action by getting water inside them. This generates a suspension fault code indicating that the sensor is out of range or that a valve is stuck. The solution is to replace the sensor with the design used on later models (part number ANR 2494). Bill O'Brien reports that ride height sensors that are giving problems can be removed and cleaned. He suggests prying the back off and cleaning with carbon tet or volume control cleaner from Radio Shack. Reseal the back with GE silicone.

Manual Operation if a Fault Occurs: There are several methods of operating the suspension manually using an external compressor or jumper wires. For details see the Air Suspension Manual Pump-up page.

Manual Selection of Extended Profile: One of the petty annoyances of the air suspension is that the extended profile mode, which raises the vehicle another 1.2 inches above High Profile, cannot be selected under driver control; it can only be selected automatically by the suspension ECU when it senses the vehicle is grounded. It can also be selected by the dealer's "Testbook" to make working under the vehicle more convenient. To overcome my frustration about this, and not having a Testbook", I devised a way of raising the suspension to any desired extent manually at the flick of a switch. This method is detailed in the section on Upgrade Operations How-To.

Rear Axle Links: The aluminum eyes on the chassis end of the rear axle trailing links were prone to possible failure. A recall campaign replaced the trailing links with new components.

Bushings: Range Rovers have very large suspension travel, and (especially if you use your Rover off road) all this movement eventually wears out the rubber bushings used in the suspension mounts. So, the bushings should be replaced periodically. Aftermarket manufacturers offer substitute polyurethane bushings which provide longer life and "improved handling"; this is merely a code word for stiffer suspension, translating to reduced traction and a harsher ride off road. I recommend replacing worn bushings with original equipment rubber bushings to restore the Range Rover's authentic ride and traction. Remove the old bushings with a hacksaw and push in the new ones with a large vice or a hydraulic bench press. Replace the fastenings at the same time.

The Range Rover 4.0/4.6 is equipped with a state-of-the-art four channel Wabco Automatic Braking System (ABS) specially developed to cope with off road as well as on road conditions. (The first version appeared in the 1990 Classic and has been refined since then). The system is the envy of other brands, but personally I find the its operation less than reassuring in mud or loose gravel -- you cannot lock the wheels until down to one or two miles per hour, and there is no doubt that stopping power is much reduced. The official manual assures us that this tradeoff is worth the extra "control" you get with ABS operation.

Speed Sensors Lifting Out
The ABS Fault message is often triggered by the sensors on the wheels becoming undseated. See ABS diagnosis and repair page.

Booster Pump Pump Failure
The system does not use the normal vacuum-powered booster found on most vehicles, but rather an electrically powered high pressure hydraulic pump with an accumulator which stores enough energy for 20-30 brake applications. These are common (and expensive) failure items. See ABS diagnosis and repair page for diagnostic procedures.

Alarm and Lockout Problems
If the battery is disconnected or dies (whether due to old age or leaving the lights on), the situation on a Range Rover 4.0/4.6 is more complicated than for more simple old fashioned vehicles. The problem is the all-pervasive alarm system, which is inclined to lock the doors if it senses a loss of power. When the battery is nearly dead, it can lock the doors, especially annoying if you have left the key in the car. When replacing the battery, leave one of the doors open to prevent being locked out and/or arming the alarm. In some markets where "passive immobilization" is enabled for the alarm system, you are supposed to leave the key in the ignition while the battery is disconnected. For more details, see the Battery Replacement and Upgrade Page. Afterwards, you need to put the key in the ignition to reset the alarm system and ignition transponder. You also need to key in the radio code to get it working again, and resynch the windows and sunroof. This procedure is described in the owners handbook.

Avoiding the Need for Resetting Codes
Marlon Patton recently changed his battery and to avoid having to reset the codes he kept his electrics working by jumpering the terminal clamps with another old battery during the changeover. It worked -- he didn't have to reset the codes or even worse take it to the dealer and be charged $200 for a battery change. Kevin Kelly recently used a similar technique to upgrade his battery to an Optima type; illustrated details of this technique and battery changing in general appear on the Battery Replacement and Upgrade page.

Virtually all non-engine functions (and even enablement of engine cranking) on the new Range Rover, from the windows to the suspension, are either controlled or monitored by a computer known as the Body Electrical Control Module ("BeCM"). Its tentacles are omnipresent. This electronic "brain" is also the one that supplies most of the 150 possible messages to the vehicle's Message Center alerting the driver to all manner of vehicle functions and malfunctions. When all that wizardry is working according to plan, everything is bliss. However this expensive (about $1000) little box full of electronics and microprocessors is one of the few ECUs in modern vehicles that seems to have a solid reputation for failing. To be fair, at least some of the "failures" have been due to the operator not understanding the complex BeCM functions, and there has actually been nothing wrong. This is known to be the case where BeCMs have been replaced for supposedly malfunctioning reverse mirror dipping. Also, it should be said that most BeCM failures do not disable the vehicle, but result in minor annoyances such as lights turning on (or not turning on) etc. For these kind of p[roblems, if you have the time and inclination, with a modicum of electrical knowledge, there is a fair chance you can diagnose and fix the problem yourself. Full details of how to do this appear in the repair operation section on the BECM Operation, Diagnosis and Repair page.

Nonetheless, the BeCM has not acquired its Lucas-like reputation for nothing. One owner reports that "My 96 4.0 locked me out...... something to do with the BECM going into anti theft mode... So I am being told, no lights, no check engine light no sirens nada! I am able to open the car normally, the radio works, the windows etc.....It just won't start." The computer had gone mysteriously into theft mode. Fortunately in his case his mechanic (Larry at Four Oaks Garage in Santa Monica) was able to reset it in all of 5 minutes. No details are available on how he did it -- if you know how to do it, please write in!! (Update 2004: From bitter experrience we now know he may well have used the Emergency Key Access (EKA) procedure described under Alarm System problems above and in more detail on the the Key/Remote Problems page). Most cases I have heard of were not so easily resolved. I personally am aware of one vehicle that was disabled for weeks at a dealer while the BeCM was swapped and other steps were tried to figure out its problem, apparently another case of something to do with the alarm system deciding to prevent the engine from starting.

If this sort of prospect is alarming to you, make sure you buy that extended warranty plan!!

Weak Points: The cooling system hoses and thermostat seem to have been a weak point on early Range Rover 4.0/4.6 models. Leaks from the cooling system were common, and a recall program was instituted to cure them. Culprits included the radiator top hose and the thermostat housing. I have heard of head gasket coolant leaks even on 2000 models. In my own case, there was a very slight leak from the thermostat housing (which was replaced as part of the recall work).

Preventive Maintenance: Range Rovers have aluminum engines, so special attention to the cooling system is called for in order to avoid unpleasant meltdowns in the case of severe overheating. Since I use my Range Rover for desert off road expeditions (sometimes in very hot weather) and for pulling a 3,500 lb travel trailer on hot summer vacations, I try to keep the cooling system in brand new condition. Recently, nearing 100,000 miles on the odometer, I noticed my temp gauge climbing a little under 100 degree conditions (off-road climbing in low range or on-road during long uphill trailer towing). I asked the dealer to check the radiator and the viscous fan clutch. The flow was indeed slow through the radiator and the fan clutch was weak, so both were replaced as a precaution. These things might not even be noticed under normal circumstances, but early replacement of such items keeps the Range Rover able to master extreme conditions without even breathing heavily.

Coolant Temperature Sensor: Simon King reports that overheating of his 4.0 on hot days with teh A/C on turned out to e caused by a bad temperature sensor ground, presumably not allowing the auxiliary fans to come on.

Heater Core O-Rings: The heater core on the 4.0/4.6 is an improvement over the Classic, and does not usually fail catastrophically. However, leaks of coolant into the right hand footwell commonly occur after a few years and are usually caused by failure of the O-ring seals that connect the heater core to the engine cooling system. Mine started leaking around 130,000 miles, noticeable as a slow loss of coolant that had no obvious source in the engine compartment. Accessing the O-rings is tricky, involving a lot of labor to remove and replace large sections of the dash. In my case the dealer charge for replacement was about $400 (the O-rings them selves cost only about $10) but see the Repair Operation Details section for shortcut methods to fix this problem .

Rubber Hoses: All the hoses on earlier 4.0/4.6 models were replaced by Land Rover as part of cooling system recall programs. However, in Range Rovers as in any vehicle, they should be replaced about every 3 years as preventive maintenance. Don't forget the heater hoses and the small diameter hoses which go to the filler reservoir (see "Radiator Overflow Hose" below) and to the air intake manifold to maintain the incoming air mixture at the right temperature. These leak too if neglected. A great bargain that includes the thermostat and just about every hose is available from the dealer for about $80 as a special recall parts kit.

Radiator Overflow Hose: Kevin Kelly reports that he had a slow leak from the hose that went from the top of the radiator from the overflow tank. The guys at the dealer parts counter told him that this hose fails often just as his did where the rubber end connects to the plastic hose at the end nearest the radiator. Land Rover has redesigned this hose four times since 1995. The current part number PCH117140 is to be used in place of ESR2929, ESR2568, and PCH115630. This photo shows the new and improved hose next to his old leaking hose.

Serpentine Belt: This drives, among other things, the viscous coupled fan, and is therefore a vital component in the cooling system. It should be replaced as soon as any sign of aging/surface cracking or any slight squeal is heard. The water pump and fan are driven by the smooth back side of the belt, which can easily slip. Replacement is very easy; for details, see the Serpentine Belt Replacement section of the Repair Operation Details page.

Radiator Clogged Internally: As on any vehicle the radiator tubes will gradually get clogged with corrosion etc, reducing cooling efficiency twofold by slowing down the flow of coolant through the radiator and reducing heat dissipation to the fins. Simon King reports that some aftermarket aluminum radiators seem particularly prone to this, and the OEM copper ones less so. Soren Jensen reports he had his clogged 4.6 radiator "rodded" for under $90 (any radiator shop will do this), but be alerted that the plastic tanks on the end of the radiator have to be removed and replaced to do this, and can get cracked in the process, necessitating buying a whole new radiator anyway. I tried this process on my Classic once and found the "cure" was only temporary so now I always replace the radiator completely when cooling efficiency starts to decline. For lowest cost sources of new radiators see the Cooling System section of the 4.0/4.6 Parts Sources page.

Radiator Fins Plugged Up: If you go off-road a lot, especially in the desert, it is worth periodically cleaning out the debris accumulated in the radiator cooling fins. Driving on roads with tall vegetation between the wheel tracks deposits lots of seeds in the radiator and air conditioning condenser, and in the space between them. This has a significant effect on cooling efficiency. To remove the debris, it is best to unclip the plastic cowl from around the cooling fan and remove the metal cover that supports the bonnet latch -- then you can see down between the A/C condenser and the radiator. Releasing the lower radiator mounts (two bolts) allows you to lift the radiator up and push it backwards a bit (without disconnecting any hoses) so you can get an air or water hose into the gap between it and the A/C, transmission and oil coolers. Ron Beckett advises that the air hose solution is best, since some seeds expand when you wet them with water, causing them to get even more jammed in!

Radiator Leaks: The radiator will eventually leak, most likely around the joints between the core and the sides. New original equipment radiators are much less expensive than on the Classic, and well worth the money. I once tried having a local radiator shop replace the core on my Classic, (about half the cost of a new radiator), but the repair only lasted a year.

Radiator Flow: Over the years any radiator gradually becomes plugged with internal deposits. Mine lasted about 95,000 miles before a test showed reduced flow and replacement was in order as a preventive measure.

Thermostat: The 4.0/4.6 has a new, improved and more expensive thermostat with its own housing, mounted behind the radiator. Thermostats can fail open, closed, partially open, or intermittently. Failing closed will lead to overheating, and on EFI systems (especially OBDII ... '96 and newer) can lead to rough running due to overfueling.You can tell if the thermostat is opening by feeling the top radiator hose when the engine has warmed up from cold; it should be warm, indicating coolant is flowing freely through the system. On startup, if the top hose starts off mildly warm and only heats up slowly, it may be a clue to a stuck open thermostat. Normal operation is to start cold, stay cold, then rapidly heat following thermostat opening.

Water Pump: My water pump started to make a whining noise from its bearing at 36,000 miles and had to be replaced to effect a cure. Rebuilt ones are available through the Land Rover Dealer network for about the price of a new one for the Classic.

Viscous Fan Clutch: This clever device acts to drive the fan only when the engine is hot. It is far more effective than electric fans that turn on when the engine is hot (although the Range Rover has these too as an extra measure of safety and to ensure air flow when idling). An engine-driven fan develops several horsepower, pulling far more air though the radiator than any electric fan. As a vital link in the cooling system, the viscous fan clutch should be checked periodically. Mine was found to be a bit weak at about 100,000 miles, so was replaced as a preventive measure.

The most common problem with the cruise control is gradual falling off of performance due to air leaks in the vacuum tubes. The tubes can easily be replaced with generic rubber tubing. See the cruise control repair page for more information.

The damper strut on the cubby box lid is prone to failure. Kevin Kelly recently replaced his, and reports that the part number is BTR6776, costing $30.21 at the dealer. The bottom of the shock is riveted on to the cubby box so has to be drilled out. Kevin decided to use a nut and bolt with a couple washers when he put it
back on rather than a pop rivet (see photo).

Ron Beckett had a strange noise from the rear differential at about 80,000 miles. It turned out to be due to two missing teeth on the crown wheel. Ron reports: "The noise first occurred some months ago. I was driving on road and I heard the chuff-chuff noise faintly in the background (windows closed). I thought I'd picked up something in a tyre. I pulled all the wheels off and found nowt. I tried driving with first the rear left window open, then the front left a window open, the right rear window open, and lastly the driver's window open - always listening for a reflection of the noise back from freeway walls etc. I couldn't locate the noise. I even bought another wheel and tyre (cheap) and put that on each corner in turn. No difference. The noise persisted and was at wheel speed - not propshaft speed. Perhaps I became used to the noise even though it was there still in the background, and I paid less heed. However, lately it become much much worse and obviously there was a problem. A previous oil change and showed the diff oil to be black, this time the oil was bright silver. It was clearly audible with the windows closed and was now audible when reflected back off the walls. It wasn't a tyre noise or something in the tyre. In fact, my mechanics thought I was being overly sensitive." When the diff was taken apart the two missing teeth were found, so Ron had the whole unit rebuilt.

As on the Classic Range Rover, the electric door locks on the new model are not immune from failure, although it happens less often than it did on my previous Range Rover. (It is nice to be able to go on a desert trip for more than one day without one or more of the electric locks failing due to dust in the manual lifters, as they did on my Classic). When they do cease working, it can have annoying consequences for the alarm system so it is best to fix the problem immediately. Mine turned out to need a new actuator (don't even ask about the price).

Door Lock Malfunctions:
Jim Harringer had a problem where both front doors on his 97 4.0SE failed to lock on command from the remote. Other doors locked, and the alarm activated, but the front doors remained unlocked. "This lead to many embarassing incidents where my wife walked up to the truck at the grocery story and opened the door before i got the alarm disabled: HONK! HONK! HONK!,,etc." Jim's local dealer said both front door latches needed replacing: $550 per door, parts and labor. Jim bought an bought an ETM (Electrical Troubleshooting Manual), and spent a Saturday staring at the inside of his driver's door. Sure enough, it seemed like the little motor in there was bad, so he ordered two latches for $219 each/ They had different connectors, but worked! Since Jim's report, others have related similar incidents including being unable to open a door from inside or out even with the mechanical handles.

A related problem is when the doors randomly lock and unlock for no apparent reason. Nathan Bailey had this problem: "Most often it happens when the car is sitting in a parking lot or our driveway, but it has even occured when we are driving. If you lock the doors either with the remote or from inside the car with the button this stops the problem. The dealer thought it was a bad door lock, but was hesitant to replace one when they were not able to duplicate the problem while the car was in for one of its many service visits. The dealer finally figured out the issue -- it was the driver's side door latch. Once they replaced the item ($600.00 parts and labor, thankfully I purchased an extended warranty) the problem was solved. Since the latch has been replaced we have had no occurance of the issue."

Tailgate Won't Open:
Rafael Herbosa had a strange problem where suddenly the tailgate could not be opened by the switch, and the passenger front door seem to not respond. He reports "I saved myself $700 of quoted repair/replacement! I found out (and thanks to the workshop manual, I managed to remove the panels without breaking anything) a wire was accidentally cut, cutting off power to the tailgate switch. The window as it was being rolled down manged to 'swipe' that wire. All is working now."

More Information
When these problems do happen, the repair is not that difficult and doing it yourself will save you about $400 in labor. For details of these repair operations see the pages on "Door Lock Failure: Getting the Door Open" and "Door Lock Failure: Replacing the Latch".

A related problem is malfunction of the alarm system which can also lock you out or stop you from starting the vehicle. See BeCM problems above.

Although the 4.0/4.6 has much less slop in the drivetrain than the Classic, it is not immune from problems. Mine has a noticeable clonk that emanates from the rear axle when shifting from forward to reverse and vice versa, and one reader recently had the same problem in a brand new 2000 model. At least in my case the sound was caused by a loose fitting rear axle splines -- they came that way from the factory. The real solution is replacement with new axles; a less expensive one is taking out the axles, inserting some appropriate "goo" (Loctite) in the splines, and reassembling them.

This is really just another Land Rover quality control problem. If it happens to you, insist on getting it fixed under warranty. In my case, the mechanics were unable to even notice the sound; you may need to take them for a test drive to make sure they "get it".

The 4.0/4.6 is just as good a "leaker" as the Classic, although it lacks the most intractable leaks like the steering box. Even some of my under-vehicle inspections of brand new vehicles at the dealer's have revealed a pool of oil on the ground, indicating that British manufacturers have not lost their touch. If your RR doesn't leak it is probably empty! (Just kidding). Here are some of the known leak points:

Cooling System: The cooling system was subject to a recall campaign which comprehensively replaced a myriad of hoses under the hood. Mine leaked at the thermostat housing, which was replaced as part of the recall. A few owners reported rapid and serious coolant leaks before this fix was announced. Even year 2000 models have been known to have coolant leaks through the head gasket. Unlike the Classic there is no special sensor in the auxiliary coolant tank for low coolant level, so if the gauge starts to rise, investigate the cause. If coolant leaks into the vehicle's interior, check out the heater core O-rings -- see this link.

Oil Pan: Like most British cars, the design is intended to drip some of the engine oil on the ground so you know it is not yet empty, and to help replenish the Earth's future oil reserves. I have had to replace the oil pan seal annually.

Oil Pressure Switch: Up to late 1997 models this switch, which senses low oil pressure, was subject to leaks around its O-ring seal. It was subsequently replaced with a revised version with a better seal.

Front and Rear Pinion Seals: These seem to have replaced the steering box on the Classic as the most notorious oil leakers. Both front and rear pinion seals have leaked and had to be replaced on my 4.0, and I have heard of others with the same problem.

Blocked Crankcase Breather: If you find your Range Rover has a major problem with oil leaking out of everywhere it could be that your engine is pressurising due to being unable to breathe. To remedy this problem remove and clean the breather located on the tappet cover.

One of the fuse boxes is situated in the engine compartment just behind the battery. Faults have been known to develop here, probably due to corrosive vapors from the battery making their way into the fusebox. Symptoms are discussed more fully on the Fusebox Repair Page but can include anything from HEVAC problems to a "Gearbox Fault" message or entire vechiole power blackouts. Keep your battery terminals clean and the battery maintained to avoid this problem.

Chris Schaeffer, an ex-dealer mechanic, reports that the most frequent immediate cause of burnt out terminals on the fuse box is clogged pollen filters imposing additional load on the climate control system blowers -- changing the pollen filters (see the Pollen Filter Replacement page for details) more frequently than the recommended 30,000 miles may prevent this, especially in dusty areas. Ron Beckett suggests that some of the corrosion problems might be caused by coolant spillage when filling the header tank - or overflow from the header tank upon removing the cap when the system overheats. Ron has accidentally spilled water into the fuse box this way; the evaporated coolant leaves a residue.

If the unit does fail, you can replace it but the part is fairly expensive (US$260 or A$380). However Ron Beckett provides an illustrated procedure for repairing the old one on our Fuse Box Repair page.

The switch on the dash that opens the gas cap lid has often been known to fail -- even causing vehicles to be towed into the dealer through inability to gas up. If this happens to you, remove the right hand side panel in the load space so you can reach in and operate the latch from the inside by hand. If you are concerned about this problem occuring, you can take preventive measures by a) getting an updated switch installed and b) attaching a string or wire to the inside of the latch in advance, leading it out through the access door at the rear of the load space side panel. Rafael Herbosa had his first romance with his Range Rover when the gas filler lid would not open. He reports that he he modified the approach recommended here -- instead of adding a string, he bypassed the electrical circuit and created a nice small push button switch that activitates the actuator and wiring tapped on the rear light. His approach and others are detailed on the Fuel Filler Switch Fixes Page

One interesting incident I experienced was the appearance of the "gearbox fault" message every time I went round a sharp right hand curve. The problem eventually proved to be a loose connector in a part of the harness that connects to the electronically controlled transmission. I have since heard from several other owners with the "Gearbox Fault" message. It apparently indicates that voltage to the transmission selector mechanism is insufficient. Another cause is failure of the transfer box ECU to communicate with the BeCM due to a bad connection or connector.

A stiff gearshift (usually showing up first in shifting from D down to 3, 2 and 1 -- with D, N, R and P still OK) can be caused by the selector cable binding. Removing the cable is about an hour's job, involving removing the center console so you can get at the top end of it. Getting at the bottom end is easy -- one of the benefits of air suspension is you can lift the car for relatively easy access to anything underneath! (But, remember to leave the tailgate open to prevent the suspension from adjusting itself while you are underneath!) The job is described in the shop manual, so study this up before starting. Unfortunately, reports Barry Higginbottom (who kindly contributed this information), the cable is not available as a separate part from the dealer -- you have to buy the whole asembly (FTC4478) including the gear shifter itself, about US$400 worth. So, Barry spent a couple of hours to draw the cable from the outer sheath, clean it up, get rid of the kinks and give it a good lube with silicon spray. He did not use grease on the cable as it appears to be sheathed in PTFE. Care is needed not to lose the 'E' clips holding the cable together. Initial results were encouraging!

Both Land Rover mechanics and owners of new 4.0/4.6 Range Rovers have reported leaking head gaskets to be a common problem. Even the later model years were susceptible to this problem -- I met an owner of a new (at that time) 2001 4.6 who had the same problem. The gasket usually leaks coolant at the rear end of the head, where a cooling channel comes up from the block between the rearmost cylinder and the rear edge of the block.

The official repair is to replace the offending gasket, unfortunately an expensive job (at least $2,000 at the dealer, who will do both gaskets while the engine is apart). On the positive side, I have not heard reports of the problem recurring after being fixed, so perhaps it was a factory defect due to poor quality control.

If you catch the problem fairly early it may (at your own risk!!) be worth having a shot at curing it using one of the newer proprietary block sealer compounds based on sodium silicate ("water glass") that you pour into the cooling system. The theory is that the compound gets forced into the crack and any air that gets past it dries it out and turns it into a glass-like ceramic, slowly building up layers of glass to seal the crack. Whether this will work if only the coolant to atmosphere seal is broken I don't know. I have read at this link that MOPAR antifreeze contains a small amount of sodium silicate to seal small cracks as they develop. The better brands of sealer have a certain amount of metal (usually copper) added to strengthen the resulting ceramic seal and improve heat conduction to avoid hot spots. Otherwise, the glass might simply melt under hard driving conditions. Usually you have to completely drain and flush the cooling system before and after adding these sealers -- if not the sodium silicate apparently reacts with the glycol in the coolant and gums up the cooling passages completely. Another down side is that these compounds tend to clog up heater cores, so if you try this it might be worth temporarily replumbing the heater hoses to bypass the heater core while the goo is in the engine.

If you have had success with these or any other solutions that avoid an actual head gasket job, please email me and let me know of your experience!

Those heated seats on the Range Rover are really appreciated in cold weather -- but unfortunately they stop working all too often on the 4.0/4.6. There are separate heating elements in the seat base and back, and the culprit is usually the one in the base being burnt out. The element is an integral part of the seat cushion and a little tedious to remove and replace. However ingenious owners have found short cuts. For full details of diagnosis and repair see the Heated Seat Repair page.

Coolant fluid appearing on the floor in the footwells can indicate a blown heater core. If it is only in the right hand footwell, it can indicate leakage of coolant from the O-rings that seal the heater inlet and outlet pipes. For details on how to fix this problem by accessing the o-rings through the glove box area (without taking the whole dash apart as suggested in the official manual), see the heater core o-ring replacement section on the Repair Details section. For right hand drive models (UK, Australia, New Zealand, Japan), the officially prescribed procedure is even more horrendous, involving about 12 hours of labour including removal of the steering column. For instructions on the shortcut procedure on these models, see the heater core O-ring replacement page.

Throttle Position Sensor: Problems such as fast or erratic idle or stumbling can be caused by a bad Throttle Position Sensor (TPS), causing the wrong signal to go the ECM which in turn will tell the injectors to send the wrong amount of fuel. For example, the ECM uses the lowest position ever seen as the idle setting, and if there is any drifting occuring in the sensor it can throw the idle setting off.

Idle Air Control Valve (Stepper Motor): This does not cause as much trouble on the 4.0/4.6 engine as it does on the Classics, but can still play up and cause surging or other idle problems when it gets gunked up with sludge oil from the crank case vent. Malfunction symptoms that have been reported include stalling and near stalling especially when coming to a stop. Also hesitation before accelerating when operating the kickdown.

Cleaning the unit can often restore proper operation. David's method is to hose the pintle and seat down with some throttle body cleaner (aerosol) and wipe off the coking.

Dirt Buildup in Air Intake Plenum and MAF Sensor: This is another cause of syymptoms like erratic idle, stalling, cutting out at idle and when coasting up to a stoplight and stumbling when accelerating off idle. such. SOmetimes the "check engine light will come on and sometimes not. Barry Higginbottom had this problem with his '95 Range Rover. All it needed was the air intake around the plenum chamber inlet cleaning. The build up of oily gunge around the throttle valve was sufficient to upset everything at idle speeds. A quick cleanout cured the problem. The Mass Airflow Sensor (MAF) has a passage the air takes separate from the main air flow. You can squirt WD/40, water, alcohol, and/or air through it to clean it out.

Alternator: Tony Sawyer reports that if the alternator is getting tired, the voltage/current to the coil can drop enough at idle so that the fuel injection system is getting a weak signal. This will cause misfiring. If you have several accessories running (computer, stereo, Engel fridge, GPS, ham radios, CB, etc.) it can reduce the voltage to the point where the engine will die. Once you speed up, the alternator kicks in enough juice to cover all your other goodies.

Faulty ignition wires are commonly encountered on the later models with the Bosch engine control system (1999-2002), leading to engine misfire. This is a case where aftermarket leads may actually be an improvement!

My inlet manifold gasket has been replaced numerous times due to air leaks, which can cause stalling or stumpling especially at idle.

If the instruments or the speedo become intermittent, the most likely cause are the cables and connectors feeding these from the BECM. Colin Wright found the solid yellow cable going directly to the speedometer was the problem in his case -- he tightened it up and all was well.

The 4.0/4.6 is not immune from the Lucas disease although quality control has gradually improved over the years. One interesting incident I experienced was the appearance of the "gearbox fault" message every time I went round a sharp right hand curve. The problem eventually proved to be a loose connector in a part of the harness that connects to the electronically controlled transmission. Another incident occured when crosstalk suddenly developed between the cruise control switches on the steering column and the stereo. This turned out to be due to some previous owner managing to get cola into the controller, so cannot fairly be blamed on Lucas. The main well known electrical bug is the BeCM, although I am told that most failures of this item do not disable the vehicle completely.

A common problem is corrosion of the main battery leads. For example John Rogers reports: "One of the biggest improvements that I have made is to change all of the larger power and ground cables.The worst cable was the Alt to the Starter. It looked good, but no current could get through. All of the dead battery/charging problems went away for good."

Ignition Leads
Misfiring, with the accompanying rough running, power loss and even stalling, is much less common in the 4.0/4.6 than in the Classic. When it does occur, the prime suspects would be the ignition leads as on any vehicle. Peter Vorwerk of Switzerland had these symptoms on his 1996 4.6SE. After inspecting all the air-intake system and the throttle-position sensor he checked also the camshaft-sensor but didn't find anything strange. Noticing a "clickering" sound, he switched off the light in his garage and could see sparks flying around ignition-lead #2. The solution was a simple replacement with a new lead set. Update 2006: After another two years and 100,000 km, the same symptoms recurred and were cured by another change in leads.
Note: For some reason, 1999-2002 models with the Bosch ignition system are particularly prone to ignition lead failures.
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Crankshaft Position Sensor or Ignition Coil
If the ignition leads check out, other causes can be the crankshaft position sensor or failure of one of the 4 coils in the coil pack. Details of the latter problem appear on the Ignition Coil Diagnosis and Replacement page.

A common problem is a rattle coming from the heat shield on the center muffler. Later replacement mufflers have more secure heat shields, but instead of buying a new one you can stop the rattle simply with a makeshift clamp around the entire muffler and heat shield. More detail is given in the Catalytic Converter and Muffler Repair Page.

It is not uncommon for half the display to appear to stop working on the dash where the mileage and other information is displayed. Usually, you can still see the numbers, but just barely. This problem is caused by one of the bulbs going out which light the display from behind. For repair procedure, see the LCD Display Backlighting Repair Page.

The idler pulley on the engine's serpentine belt system was subject to a recall campaign due to a possibility of causing breakage of the belt. Make sure your recall has been done if applicable. If your belt tensioner missed the recall or wears out again, replacement belt tensioner assemblies are available for about $70 at Import Parts Bin.

Many people complain that Range Rovers are underpowered. A company called Superchips Inc produces performance upgrade chips for vehicles previously considered "unchippable". They have an enhanced chipset for the Range Rover 4.0SE which requires 2 chips instead of one (due to the 4 coil ignition system) and boosts output by 19 bhp and 30 ft-lb of torque. RPI Engineering, the Rover V8 specialists, have many upgrade options and are working on an upgrade kit that will work out cheaper than a new short engine for those already owning 4.0's wishing to upgrade to a 4.6. It is estimated that the cost of the kit will be £650.00, including a new crank, bearings, pistons, rings & con rods etc.

Range Rover sound systems are supposedly designed to withstand the rigors of off-road use but I personally have found they need replacing or repairing at regular intervals. One annoying feature is the need to enter the 4-digit radio code every time the battery is reconnected after some repair operation. Some people have reported frustration in attempting to get the radio working again; for example John Rowntree had problems after the battery was out for an extensive service visit; one of the buttons did not seem to work. After a certain number of wrong attempts, the system freezes and you have to leave it on for an hour before trying again. John found that indeed, leaving it on for 90 minutes was the key. It took the code fine at that point.

Another common problem is the dimming of the LCD panel on the radio if one of the bulbs illuminating it from behind fails. The procedure for replacing the backlight bulbs is detailed on the Radio Display Backlight Bulb Replacement page, but is a slightly tricky operation (sometimes resulting in further damage from the soldering iron such as burnt LCD microchips and connections).

These and other radio problems can of course be fixed by paying the $1500 requested by the dealer for a new radio, but I recently discovered that John Monaghan of Roverville Radio Repair & Exchange provides top quality radio work with all genuine factory parts at a fraction of Land Rover's prices and down time. John specializes in the Clarion Diversity units (AMR 2672) used on all 4.0/4.6 models from 1994 through 1999.5, and the RTC7788 model used on Defenders. He also buys these units in any condition and sells fully reconditioned units for $425 (a far cry from the $1500 Land Rover price). He actually repairs these units for many Land Rover dealers who do not want to wait several months for the official Clarion repairs -- John's usual turnaround time is a splendid 24 hours from the time of receipt. John has kindly agreed to help sponsor this website, so if you use his services please mention you were referred by Rangerovers.net.

The seat belt warning buzzer on the 4.0/4.6 models is excessively loud, intrusive and irritating. Kevin Kelly shares his procedure for disabling this irritating noise on our Seat Belt Warning Disabling page.

All Range Rovers are equipped with a formidable range of electrical sensors, monitoring every function of the engine and body. Some provide early warning of potential problems before there is any danger of major engine or other component damage. In my experience, if a warning signal appears in the vehicle's message center it is more likely to be caused by failure of the corresponding sensor than of the system it is designed to monitor; however it is always advisable to check out the actual cause as soon as possible just in case. Eric Fournier found that sensors such as the fuel pressure sensor (in the fuel pump assembley) that caused stalling on the 4.0 engine in his late model Disco can often be disconnected to get you home. This applies to all modern EFI engines -- the ECU usually has a limp home mode that will use whatever other sensors are still working. He reports that the Throttle Position Sensor, Mass Air Flow Sensor and Crank Position sensor are absolutely necessary to the running of the engine. All other sensors can be disconnected and the engine will still run albeit with default values (which means the engine won't necessarily run as intended in all environmental conditions). These not so crucially needed sensors include cam position, fuel temp, air temp, coolant temp, knock and O2. Eric now has a spare fuel pump to bring along since that pressure sensor is part of the fuel pump assembly ($400 - ouch!).

Front Suspension Height Sensors
Sensors are employed in the electronic air suspension system to monitor ride height. The front ride height sensors have been known to fail, especially due to water exposure and retention, resulting in a trip home on the bump stops. A replacement sensor of a new design can be fitted.

ABS Wheel Speed Sensors: On one off road trip I lost most of the available stopping power on muddy surfaces through overcompensation of the ABS system. On another, I got traction control fault messages. The problem turned out to be a misaligned right rear wheel speed sensor. It seems that the sensors can pop out of position; when installing them it is important to push them all the way in. Interestingly, the workshop manual says the ABS sensor bush must be replaced if the sensor is removed. This could be to prevent subsequent movement of the sensor. In any case, a periodic visual inspection might identify this problem before it causes a hazard.

Bonnet Open Sensor: I found the failure of this sensor annoying on an off road trip when the "bonnet open" message (accompanied by the inevitable irritating loud beep from the message center) kept appearing whenever I drove over rough roads. Fortunately its replacement is not difficult. One owner offers the following advice to try before even replacing it: "Loosen the two bolts holding the LHS bonnet catch (facing the car) and adjust the bonnet catch forward slightly and then retighten; this will ensure a better activation of the microswitch".

Crank Position Sensor: The operation of the ignition and EFI systems is synchronized by two sensors that monitor the crankshaft and camshaft positions. Failure of one of these could cause the engine to cease running entirely, and the crankshaft sensor in particular is known as a cause of misfires. Barry Higginbottom had a misfire problem on his 4.0SE when cold that went away when the engine was warm. It was eventually solved by an experienced and enthusiastic LR dealer technician who knew exactly what the problem was and without the aid of the TestBook! It took all of 10 minutes and about GBP20.00 for the parts.

CD Changer: The 6 disk CD changer is supposed to be shock mounted to withstand off road use, but mine has had to be repaired 3 times for about $150 per time. Typical symptoms include skipping while playing, and jamming so the CDs cannot be changed or removed.

Subwoofer Thump: Some owners have experienced a thump heard through subwoofer assembly. There is a connector in the left side kick panel that gets corrosion in it and causes this thump noise. The fix is to put new connector pins in, run a new wire to the subwoofer from the audio head unit, or put jumper wires across the connector.

Hardy Neale reports the lighting of his SRS lamp and warning message 'airbag fault' appearing. "Over 3 weeks it only went out 2 times. I thought it may have been the 'rotary coupler' (expensive twisty wiring bit inside steering column) but no - much easier than that. The testbook diagnosis revealed it was the RHS circuit at fault. This could mean either steering wheel (RH Drive) airbag or side of seat airbag circuits. The SRS wiring connector beneath the seat appeared connected but just needed a squeeze to complete the circut. I had an upholster repair part of the seat some time ago - he must have disturbed the connector just enough for the circut to fail some time later. So even though the connector look connected - it wasn't. What a relief !" Richard Corbett reported experiencing the very same symptom and solution -- on his the fault message would appear every time he adjusted the seat position, disturbing the plug!

Several owners have reported stalling either when coming to a stop or in cold temperatures. Things to check if you have these symptoms include:
Ignition Coils: Check to see if a whitish or blackish substance is exuding from them. For more details see the ignition coil diagonosis and replacement page.
Throttle Position Sensor: Inspect to see if seals are rotten or if it is full of oil.
Intake Air Leaks: Intake manifoldleaks or perished rocker cover breather hoses
Air Bypass Valve/Stepper Motor (see Idle Air Bypass Valve section above)
Crankshaft Position Sensor (See Misfiring section above)

Basic Electrics:
The 4.0/4.6 is no more subject to starting problems than any other vehicle, but a few things are handy to know just in case. Current is supplied to the starter solenoid by Relay 16 in the engine compartment fuse box. The relay is supplied by a 30 amp fuse (MF2) in the same fuse box, and is activated by a ground signal from the ignition switch via the BeCM. The fusebox lid gives a key to the relays -- look for one with a starter motor symbol on it. If you cannot hear the relay click when the ignition key is turned to "start", or you suspect it is bad, you can pull it out and jumper pins 30 and 87 to get started.

The fuel pump and injection system is supplied by Relay 12, fed by a 10 amp fuse (F39). These components are also in the engine compartment fuse box and are worth checking if the fuel system is suspected.

Richard Talley traced the starting and charging problems on his 96 Range Rover to a highly corroded, oil-soaked cable running from the battery (positive terminal) to the starter. This caused sufficient voltage drop to affect both starting and charging. Most likely, the connection between the crimped lugs and the cable eventually failed.

Fuel Pump & Injectors:
David Giller reported his 1998 4.6 HSE required cranking for 15-20 seconds on cold mornings before it would start. As soon as it reached normal idle, it ran smoothly. He was also getting poor mileage, and slihtly rough running. After Internet research he bought a set of Bosch purple-top injectors from Five-O Motorsports. They solved the cold starting problem completely, and the engine also seemed to run more smoothly. However, the symptoms later came back, and he found the fuel pressure was down to 20 psi rather than the rated 33. During cranking when electrical voltage dips, the pump was barely putting out any pressure at all. So the engine was not getting enough fuel to start until it reached full idle speed with the starter motor disengaged. After replacing the fuel pump, David reports the symptoms are gone again. "This time, it starts much more forcefully than it did even when I bought the car, so I feel more confident that I can claim that this was the solution. I still recommend the Five-O injectors. It did make the car run more smoothly. I would suggest that anyone with a Rover with 100k miles should consider replacing the injectors, and I feel good recommending Five-O."

Security Code:
A more unusual starting problem was reported recently by Fred Jauch -- the starter engaged and the engine turned if he manually wired power to it by bypassing the relay, but not otherwise. After checking all the usual problems, the dealer found the engine ECU had lost its security code. The dealer said this was rare but does happen, and after reprogramming it everything was fine.

The 4.0/4.6 has a much better steering box and system than the Classic. However it is of the same basic design, and some owners have reported the steering judders upon going over bumps at speed that are so notorious and common in Classic models. If you have checked out all the ball joints and tie rod ends, the most likely cause is the steering box needing adjustment. Like the Classic, the 4.0/4.6 steering box has an adjuster on top -- this one has a screw with an internal hex and locknut. Jack up the front wheels and screw in the adjuster until there is minimal play in the steering at dead center. Then turn the wheels lock to lock to make sure there are no tight spots. The other thing to check is the swivel pin bearings, which need to be kept adjusted as per the shop manual, or replaced. Ian Dugdale (Ian at Dugdales dot com) had this problem and after trying the usual remedies (suspension bushings, steering damper, etc) he replaced the swivel pin and steering joints and that made a huge difference. Also (and this needs to be done very carefully) he tightened the steering box slightly (about 1/8 turn). Overall that made a major improvement in the driveability of the vehicle. A member of the Range Rover forum, Rundeep_32, found 90% of his steering shudder went away when he replaced his shocks (he used Woodhead units sourced from DAP which appeared to have strong rebound damping and relatively mild comression damping).

The 4.0/4.6 model shares with the Classic the characteristic of deriving its tachometer signal from the alternator. If the tach needle suddenly starts dipping to zero, your alternator is probably dead. Matt Armstrong experienced this behavior with his 97RR (followed by Traction Control Failures and Gearbox Failure warnings). After replacing the alternator all irregular behavior disappeared.

The Transfer Case ECU is a known failure item and its malfunction can cause the transfer case to lock in low or high range. Fortunately the replacement is not too expensive (compared to most ECUs).

Every 30,000 miles the transmission fluid needs to be drained and refillled, and the filter needs to be replaced. The 4.0/4.6 fortunately avoids the brilliant design of the Classic in this department, so you no longer have to remove a chassis crossmember to get the pan off the transmission in order to change the filter! There is still a chassis cross member in the vicinity, and removing it easses the transmission job but is not essential. For complete illustrated details of the transmission service operation (and timesaving tips the official manual does not tell you) see the 4.0/4.6 ransmission Filter Service Page.

If the transmission is stuck in Park, the cause can be a blown fuse (check the fusebox under the RH front seat) or failure of the brake light switch. As Gill964 reports, "The result of an inoperative switch is no brake lights which does not allow you to take it out of park. The brake switch is located just behind the brake petal about an inch long and black. Replacement cost less than $40 US".

Sticky valves are a more common occurrence in the 4.0/4.6 engine than they should be. The problem seems to be faulty clearance tolerances in the valve guides or carbon buildup at the bottom of the valve stem. To reduce the incidence of the latter problem, Land Rover recently introduced a new valve design with a "step" in the bottom of the stem designed to make it harder for the carbon buildup to climb up the stem over time.

Although the 4.0/4.6 engine is renown for being exceptionally smooth, there were engine vibrations reported on some early build models. With the vehicle stationary, if a vibration is felt around 3500-4500 RPM, the engine may need to be rebalanced.

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Water in the Footwell

If you have fluid in the footwell, check to see if it is coolant or just water. If coolant, see the section on Heater Core O-Rings.

If only water (almost certain if it is only in the left footwell), the most likely cause is a dislodged, blocked or leaking drain pipe from the air conditioning evaporator. Normally this drains through the floor and drips onto the ground. If the drain is still in place you might try cleaning out the tube with a piece of wire. When this leak happened to me on my Classic, it turned out that the rubber drain pipe had been dislodged, and poking it back through the firewall fixed the problem. Ron Beckett had it on the passenger side of his (right hand drive) HSE. The 4.0/4.6 actually has two drains, one on either side of the transmission, and they drain through the floor rather than the firewall as on the Classic. The fix was to get underneath and squeeze the end caps on the drain tubes to release the muck and water. The picture at right is taken from underneath the car at the rear of the transmission, and shows the right hand (unblocked) airconditioning drain on Ron's 4.6 (click on image for larger view).

Another possible cause is a badly sealed pollen filter. If the seal on the pollen filter cap is slightly off track, water can enter in fairly large quantities when it rains. For details on pollen filter installation, see the pollen filter page in the maintenance section.

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Windshield Leaks

British cars are equipped with leaks for two purposes -- to let oil out and to let water in. An example of the latter on my 4.0 was a windshield leak. An early attempt to repair it with "goo" had not worked and the only solution was to fork over $800 for a new windshield. The reason they are so expensive is the fine heating wires embedded throughout.

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Windshield Washer System

After a few years, the windshield washer system slows down in its functioning and develops leaks. The usual source of leaks is at the underside of the plastic washer jets themselves, which protrude through the hood where they are exposed to the heat of the engine, eventually making them brittle. Another source of problems is the non-return valve in the windshield washer hose about half way between the washer fluid reservoir and the jets. When this little plastic valve fails (again probably due to heat exposure), the washers might still work but have to be activated for 5 or 10 seconds before anything comes out the jets. If no water appears at all, the problem may be the pump itself. Fixing the system is very simple and inexpensive; detailed procedures for diagnosis and repair appear on our Windshield Washer Repair page.

Another problem that is not uncommon is to get the "Low Screen Wash" message even though the washer fluid reservoir is full. THe cause here is a bad washer fluid level sensor. Replacement of this i covered in detail on the "Low Screen Wash" message page.

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Extended Warranties

Due to the considerable expense of proper maintenance and repairs for the newer model Range Rovers, and your dependence on the dealer for many electronic-related problems, extended warranties can be very attractive. Click here to find out more about the pros and cons of aftermarket warranties for Range Rovers.

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Parts Sources

Until recently the local dealer was the best bet for parts for the 4.0/4.6 models -- this is still the case for the more obscure parts. If you patronise yours frequently, they may give you a discount. However, most aftermarket parts sources now have a good selection of parts for this model, as the situation has improved a lot in the last couple of years. For a lot more parts information please see the Range Rover Parts Sources section of this website. Other sources of parts information:

4.0/4.6 Aftermarket and Generic Parts Sources page on this website
Atlantic British stocks a wide range of 4.0/4.6 parts, genuine and aftermarket, and now has a Range Rover 4.0/4.6 catalogue.
Import Parts Bin -- (AKA Speedycarparts.com) (Select "Rover Parts") Guaranteed lowest prices, free shipping -- for specific suggestions see the RR Parts page.
Car Cannibal -- Specialize exclusively in used and rebuilt Rover Parts. All parts fully warrantied.
Disco-Tech Industries: Engines plus Genuine, OEM & Aftermarket Parts. US buyers can take advantage of Canadian pricing.
AutoPartsGIANT.com -- Relatively few RR parts but the ones they have are at unbeatable prices. For specific finds see the RR Parts page.
Partsamerica.com -- Internet outlet for Kragen, Checkers, Schucks, Advance Auto Parts (common service items, filters etc)
The Rover Connection in Salt Lake City, Utah, has very good prices on all genuine parts and accessories for the 4.0/4.6 models.
Rovers North can get any genuine part including ones only used in the UK (eg the full selection of alloy wheel options).
Europarts has a good selection of parts.

Other Information Sources

Range Rover Aftermarket and Generic Parts Sources
Repair Operations How To:Beyond the Shop Manual
Upgrades (Mechanical & Electrical)
Maintenance Operation Details
www.dollar.com for an inexpensive rental car while your Range Rover is in the shop!
Alldata repair info, Rover tech bulletins etc
Autologic Diagnostics "Testbook"- like interface for 4.0/4.6 diagnostics
BeCM Problems/Symptoms/Rebuilding (Car Electronic Services)
Cooling System: Avoiding Problems (Rovers North Tech Tip)
Climate Control Troubleshooting (by David Sparkes)
ECU/Airflow Meter Symptoms (Range Rover Register)
EFI Problems, Diagnostics and ECU rebuilding (Car Electronic Services)
Emergency Procedures (Some info from ETS Manual, from LR Club of Luxembourg)
MAD Mechanic (Motor And Diagnosis) a lot of useful diagnostic info for modern vehicles.
Pollen Filter Replacement on 4.0/4.6 (British Pacific Tech Tip)