RangeRovers.net Forum banner

1 - 10 of 10 Posts

·
Registered
2010-2012 Range Rover MkIII / L322
Joined
·
22 Posts
Discussion Starter #1
Over the last couple of months I have been having the P0442 fault and of course it is inspection time so I need to resolve this...
I have been reading every post I could find and of course I checked the gas cap first.

The strange thing is when I plugged my IIDTool in the battery says 12V, when I turn the ignition on it goes to 11.7. I also have a U3003-16 and -17 faults.

It just seems like 12V or less is just too low and I am thinking maybe this is giving the P0442 fault because it seems like I remember having all of these faults each time after I reset the faults.
When I crank the engine I get 13.8 volts from the IIDTool.

I replaced the battery last October with a H8, 900CCA.

It just seems like a coincidence that I am reading a low voltage with a Battery voltage fault. It is an Autocraft battery, so it is possible that it is bad.

Any insight would be appreciated... could not find any info on the U3003 faults.

Regards
 

·
Registered
2006-2009 Range Rover MkIII / L322
Joined
·
1,191 Posts
Thats a catalyst efficiency below threshold on Bank one (passenger side) code. Either you O2 sensor if going bad, or your Cat is about expended. How many miles on it? U3003 is a network fault code, for battery voltage.
 

·
Registered
2010-2012 Range Rover MkIII / L322
Joined
·
22 Posts
Discussion Starter #3
The error says " Evaporative Emission System Leak Detected (small leak)", so how does that equate to catalyst issue. The car has 88K miles. It will display the tighten gas cap message a couple of times before the light comes on.
My reasoning is that if the battery is weak then when the leak test happens after the car is shut off then there may be a variation in the current reading of the pump that is interpreted as a leak.
 

·
Registered
2006-2009 Range Rover MkIII / L322
Joined
·
1,191 Posts
I looked up P0422, P0442 is the small leak detected, could be a loose gas cap, or a hole in the vacuum line that runs from the evap solenoid to the gas tank. The tank does not maintain a high enough vacuum pressure for long enough during the test. Test is only run with the fuel tank between 3/4 and 1/4 full. Check the condition of the o-ring on the gas cap, and for any amount of rust on the lip of the fuel filler neck. Mine had a small amount of corrosion right on the top of the filler neck where the gas cap screwed down onto the o ring, it was enough to set that code every so often. Quick bit of sanding with fine sandpaper took the rust off and its been fine ever since. If you need to sand cover the opening with a rag to keep any junk from either the rust or sandpaper from ending up in your tank.
 

·
Registered
2010-2012 Range Rover MkIII / L322
Joined
·
22 Posts
Discussion Starter #5
Checked the cap.... had a little rubber residue on the lip, cleaned it off, but didn't seem to be enough to create a leak... The o-ring looks good but might turn it over.
I reset the code but not sure how long it will take before is goes through a cycle.
Other thought... do you know how many warnings to tighten the gas cap you get before the light comes on... Might be an option that it goes through the test enough to set the drive cycle in order to pass inspection... Idea being that once you get the first message to tighten cap to then fill the tank to stop the test and get it inspected... at least it buys some time to find the problem without throwing money at it.
 

·
Registered
2006-2009 Range Rover MkIII / L322
Joined
·
1,191 Posts
I don't ever remember getting a check gas cap warning, just the MIL light coming on, maybe my leak was small enough to not warrant a check gas cap message, but big enough to give me the P0442 code. Might have happened, just don't remember. This code (along with the 0420 Cat expended code) are the two I hate the most because if its not the cap on this one finding the leak point can be a huge exercise if you don't have access to a smoke machine. On some early 2000's Chevy's and Toyotas the solenoid that allows vacuum to the tank can get stuck shut and give you the code as well. A couple of taps on the solenoid with a screwdriver handle fixes those, but I don't think the RR's have this problem. I even left the cap off once by accident and drove away and didn't get the code or a check gas cap message, but like I said it doesn't run the test if the tank level is greater than 3/4 or less than 1/4 full and I figured out the cap was off before it would have run the test (about 1/2 mile down the road).
 

·
Registered
2006-2009 Range Rover MkIII / L322
Joined
·
1,191 Posts
Opened up the service manual and found that it works like this.

When the ECM activates the DMTL system, it first activates only the DMTL pump motor. This pumps air through a 0.5mm reference orifice which causes the electric motor to draw a specific amperage value. This value equates to the size of the reference orifice. When the change over valve solenoid is energized, the normally open valve is closed, sealing the EVAP system from atmosphere. Providing there are no leaks, the air pump will begin to pressurize the EVAP system and the load and current draw on the pump increases. By monitoring the rate and level of the current increase, the ECM can determine if there is a leak in the EVAP system. During normal vehicle operation, the ECM energizes the heating element in the pump to prevent condensation formation and possible incorrect current readings.


Leaks are classified as:
Minor - equivalent to a hole diameter of 0.5 to 1.0 mm (0.02 to 0.04 in)
Major - equivalent to hole diameter of 1.0 mm (0.04 in) or greater.

The ECM performs a check for major leaks each time the ignition is switched off, providing the following conditions are met:
The vehicle speed is zero
The engine speed is zero
The pressure altitude (70 kPa (10.15 lbf/in 2 ) derived from engine load calculations) is below 3047 m (10000 feet)
The ambient temperature is between 0 and 40°C (32 and 104°F)
The charcoal canister load factor is 2 or less (where the load factor is a measure, between -1 and +30, of the fuel vapor stored in the charcoal canister. Where -1 is 0% fuel vapor, 0 is stoichiometric fuel vapor level and +30 is 100% saturated with fuel vapor.
The fuel tank level is valid and between 15 and 85% of nominal capacity The engine running time during the previous cycle was more than 10 minutes
The battery voltage is between 10 and 15 volts
The last engine off time was more than 180 minutes
No errors are detected with the EVAP components, the ambient air temperature and the fuel level
High range must be selected on the transfer box.
 
1 - 10 of 10 Posts
Top