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Discussion Starter #1
I have had my Range Rover for ~8 months (my first, but not my first Land Rover) and much as I love it, it suffers from some of the usual problems. At the moment it is (surprise, surprise!) the EAS!

The compressor was rather noisy and very audible in the cabin, which turned out to be a good thing as it highlighted just how much the compressor was running. I also noticed that the front end has a habit of moving slightly up and down, "dancing" if you will. Reading through the excellent EAS Troubleshooting Tips sticky on this forum I found that this may well be due to leaking non-return valves. Dutifully I ordered the o-ring rebuild kit from rover renovations.

Having finally gotten the Rover back from the shop for other issues (problematic cam shaft sensor, new head gaskets :roll: ) I rebuilt the valve block. This went well, the compressor teflon ring was examined and is fine, sadly though the problem remains. I did cure the noisy compressor though - turned out to be some missing bolts on the aft support bracket. Someone has been in this EAS box before me.

Unfortunately now the compressor is so quiet it's hard to notice the problem so I hooked up an LED from the EAS ECU connector pins (8 & 18) to see whenever power goes to the compressor. Specifically, this is what happens, whether the vehicle is at standstill or on the move:

1. Compressor runs anywhere from 20 sec to 3 minutes.
2. Front end (both sides) rises slowly, maybe a half inch.
3. Compressor stops, usually with an audible "whoosh" - presumably the pressure relief valve?
4. The front ends (both sides) then lower, with 4-5 audible solenoid clicks lasting about 5 secs.
5. The process starts all over again.

Effectively the compressor works all the time with the exception of the few seconds the front end lowers. I am worried as over time the compressor will fail or worse; there is evidence of overheating on the compressor connector in the EAS block, the supply wires and the EAS relay. Presumably this has been going on long before I got the truck.

One thing I do find odd, even if there is a leak in the valve block still, is why the compressor runs so often. Why is stored air in the tank not used until it depletes somewhat before the compressor kicks in again? The front end is only moving a little bit, so it can't be using that much air....

There is no evidence of leaks on the lines or the airbags, though sometimes the suspension settled a little over night, sometimes it didn’t

I do not have any software to read/program the EAS ECU at the moment and was wondering if anyone has any ideas or suggestions before I start laying out cash for such things, or do something silly like buy a coil conversion kit!
 

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It's sounds like you may have a problem with you either your right or left front height sensors. They could be out of sync. I had the same problem with the dancing :dance: :dance: as you described. That'll be my next guess since you've followed the sticky and it's still doing it. I'd get on this matter right away because you don't want to wear out your compressor. Also if I was you I'd invest in an EAS buddy!!! It'll save you alot of headaches from having to take it to the dealer or local indie just to clear the codes to get you off the bumpstops.
 

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1995-2002 Range Rover P38A
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Dancing up and down could also be EAS driver pack, the black square unit attached to the valve block...
But also check connections carefully, I've had a few where the pins on the plugs, lower and upper in the EAS box are pushed out as you plug in mmm plug...

also worth checking pins all round including sensor and EAS ECU, here aswell as doing the EAS valve block I use a magnifying glass, the problem isalot clearer when you use one, I harp on about the magnifying glass but it really really really does work well
 

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Discussion Starter #4
I think jonboi002 jinxed me! :) I have been having a look at the EAS again today and twice now the compressor has "seized" up. It's not terminal (yet). If I take the compressor apart and manipulate the piston by hand it starts working again.

Someone remind me why Land Rover chose such a complicated suspension system rather than coil springs??!! :roll:
 

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tbrown944 said:
Someone remind me why Land Rover chose such a complicated suspension system rather than coil springs??!! :roll:

because when it works, it ROCKS!, it just fails hard, just like rockstars....

if the dancing is mechanical, it's the NRV's or the inlet valve leaking by slightly, it's not using the air from the tank, because it's when the compressor runs that it's rising. Once the comrpessor fills the tank (which it'll never do because it's always cycling) the dancing will likely stop. Leave the drivers door open and let it run till it stops, then shut the door, it should come down and stay steady, if it's leaky valves... The pressure switch has about a 10psi band, so when tank air is used, even a little, it will trip the switch and start the compressor again. The melting on the wires is from constant start/stop of the motor, not constant running. Starting takes 4x the current, or more, of normal running.

As others stated above, it could be in need of a height sensor calibration, and as a last step, a new driver module.
 

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Discussion Starter #6
because when it works, it ROCKS!, it just fails hard, just like rockstars....
Too true, and like rockstars it fails too early in life :)

If it were a mechanical issue I could understand the dancing when the vehicle is at standstill as the front end levels itself, but surely when the vehicle is moving the air would have to be bypassing the airbag valves too....

Anyway, it's a bit of a moot point at the moment as my compressor has given up the ghost. Kaput. Now I'm running on the M.A.R.S system I bought a while back.... foresight instead of hindsight for a change!!! Seems to be working OK.

I was looking for compressors on your website and see that you're out of stock on both the OEM and aftermarket versions. When would you expect to get them back in stock? Presumably the aftermarket one is the way to go on both price and performance.....
 

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Discussion Starter #7
OK, although I have no air due to the dead compressor, I dismantled the valve block again to look at the NRV's more closely. I have attached a pic (below) and you can see that there is considerable wear on the two left hand ones - the two in the same direction in the block, which I believe are the inlet and tank NRV's.



This could very well explain air leaking past them, inside the o-ring most likely. The worst one is on the far left, which actually came out of the middle valve port in the block. Is that the inlet or tank port?

It's a good lead, but now the problem. Where on earth does one get new non return valves? :think: I have looked on rover-renovations, atlantic british etc, but nothing. Suggestions would be welcome.
 

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The NRV closest to the collets is for the tank. Yours look better than many ive seen, they can be rebuilt with JBWeld, if they were available new I'd have them listed.

I have a machine shop trying to copy them economically.
 

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Have you checked the Diagphram ? usually they have a split in them between the metal washer and the rubber, you will find it underneath the back end of the Valve block, undue 4 long bolts and take a look, if the Diagphram is ripped, it will cause Air to feed from the Compressor and come streight out again at the port to the Air tank.
I had the very same fault on my P38.
 

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Discussion Starter #10
The diapragm is in great shape. Looks to me like someone has possibly rebuilt/worked on the valve block before me at some point.

I have ordered a 2nd hand valve block and compressor off of Ebay. I know, dubious background perhaps, but buggered if I am going to shell out $1700 on all new parts for what might be a small cause. Hopefully I'll have a enough good bits (including a different valve block driver) to test with. $180 all in, so it's got to be worth a try first off then get the EAS Unlock Suite on it to see what the height sensors are reading if it doesn't turn out to be a block issue.

Sigh....
 

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Hi Tom,

ahh, you gotta love Land Rover, yes, its complicated, totally agree with Shupack, when it works its the best system out there.

When you buy a rangie, it should come with a large box of perseverance and good size pack of patience :)

just think of how much you'll enjoy it when it works.

Cheers n beers
Mick
 

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Discussion Starter #13
After a faultfinding hiatus (been at work, you know the score Mick!) I got back home and put in my Ebay compressor and valve block. The compressor runs well, but sadly the valve block has not fixed the issue. The front end still does it's hunt up and down (not much, but enough) and the compressor is working as much as it did on the original block. The "new" valve block came with a driver pack, so it's not that either.

I also got the EAS unlock suite running and as far as I can see there are no stored EAS faults and the values from the height sensors are sensible and in range of the stored height settings. It's a bit hard to tell as the software doesn't give a "live" height readings (one of the sensors might be giving a bad value only occasionally), but numerous re-scans have never shown a dodgy number.

I have sprayed out the front height sensor connections with contact cleaner too. Worked on my SRS Airbag fault, but not on this one!

So where to from here? I will probably order a second hand height sensor and try swapping out one side at a time, but beyond that the only other common component I can think of is the EAS ECU itself, but what are the odds of that being bad? I know second hand parts might lead me to more trouble, but had I bought a new valve block and compressor I would be kicking myself now.

On top of that the MARS is OK, but has a habit of leaking. I think this is because of the scratched ends of the airbag lines from the valve block seats. I don't want to cut them back until I have the 6mm airline parts my brother is bringing from the UK. Right now, I am letting the EAS pump up the suspension to height, then I disconnect the 2 connectors in the EAS box, take out the compressor relay and it holds it's height without any hard faults. Well, it actually goes up a bit all round after driving, so that pretty much rules out any leaking airbags!

Now I think about it, in all the playing around I have done I have NEVER seen a hard EAS fault. Everywhere I read people are reporting these, but oddly mine has not. Maybe I have been really careful in faultfinding in terms of key on/off etc but maybe it should have hard faulted by now and hasn't? Maybe very circumstantial evidence of an EAS ECU issue? Now I have the unlock suite, can someone tell me a guarenteed way to induce a hard fault? I can try it and see if it responds.

As you can see, I'm clutching at straws..... :pray:
 

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if you disconnect the eas pump electrically or pneumatically and then ask for a higher height (once tank is empty) then system will try to raise the vehicle but after a period should go into hard fault as it cannot raise one or more corners.Should give a Compressor fault if I remember correctly. :thumb:
 

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Dancing is typically 2 things. Leaky non-return valves, or an out of tolerance calibration. It's entirely possible the replacement block has the same issue as your original. It's not the driver as they give strange operation...

When you disconnect the block wires, the ECU is still powered and will try to change heights when needed, you'll eventually get a fault when it can't.

You mention the calibration seems reasonable, LR wasn't being reasonable When they programmed it, make a set of blocks (the heights are here somewhere) and do a full calibration. Grasping at straws will just cost time...
 

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I often see this fault,worn height sensors will often give the same output in more than one positon.So the ecu will raise or lower a corner to try to achieve a target height - all it sees is something it did not expect so it will raise or lower again,and again....
When the valve block, compressor and air springs are worn out chances are the height sensors are too.At this age I'd throw in a new drive pack too.(Thats if you want reliable EAS.)
 

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I have the same problem with my 94 HSE. I believe it is the height sensors. You can swap them side to side and then you get a brand new piece of track for the sensor to run on - effectively a new height sensor!

I'd start with that and have your calibration tools handy.
 

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Hi Tom,

at one point my 2002 was doing a little dance at the lights too, and the dealer replaced a height sensor. Now that was nearly 18 months ago and my truck had never seen a dirt road at that point in its life, so it is entirely possible that your height sensor is dodgy. I kept the old one and I cannot see any problems with it using a multimeter. I did not put it on an oscilloscope though to be thorough.

I like the Height Sensor side to side swap to begin with and then a recal of height settings. That will be a pretty good indicator of the culprit after that. Keep in mind the LR Test Book list_of_things_to_do_when_you_have_this_problem says to replace the height sensor (first in a long list of things to change and charge the customer for) If you still have problems after that then its the valves. That mars is definitely a cool addition hey.

Good luck
Mick
 

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Discussion Starter #19
Thanks for the input guys.

So, I have driven around with the valve block hooked up, but not the compressor. At NO point have I received an EAS fault. I'm going to try again and set different ride heights to ensure the tank is depleted to see if that'll do it. I also drove around with both the valve block and compressor disconnected with the compressor relay out and that does not go into a fault mode either.

Shupack, appreciate the logic, but the chances of 2 blocks having exactly the same fault? I'm going to rebuild the "new" block soon and check out the NRV's, but as you pointed out on my photos, you have seen ones in much worse condition. Plus how can I find out? I'll convert to coil springs before I fork out for a new valve block only to find that doesn't fix the problem....

I will also try swapping around the NRV's in my original block. In theory if one of them is the problem, the sypmtoms should change. Right?!

As for the recalibration, I have to say I am a bit confused. At the moment when the vehicle reaches the set height, all corners look right. i.e. both rears are at the same measured height and both fronts are at the same measured heights. Not really sure how that can be improved with a re-cal.

It's also notable that with the compressor electrically disconnected the valve block doesn't seem to make the small up and down adjustments. When connected, the compressor runs, the front end goes up (a bit) and then adjusts down again and so on. I still can't quite figure out how the air is getting past the solenoids, even if an NRV is dodgy.

Anyhew, I swap some things around and see if I can at least try and get a hard fault or change the symptoms.

Cheers
Tom
 

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tbrown944 said:
Shupack, appreciate the logic, but the chances of 2 blocks having exactly the same fault?
normally I'd agree with you, but EVERY block does this eventually. As the NRV orings get old/hard from the head of the compressor, they start to leak by.

LR BRILLIANTLY designed the tank with 2 (yes 2) isolations, the inlet valve (in to the springs, out of the tank) and the NRV for the tank. when the compressor runs, air goes through the tank NRV the right way, but also pressurizes the other 2. if they leak, air goes into the main air inlet header. Since the compressor is running, the diaphragm valve is shut and the exhaust is blocked off.

The air leaking past the NRV's into the header, will leak past the airspring isolations (they're like a powered NRV only hold air in, higher pressure in the header will leak past, slowly) and raise the rover. not sure why it's only the front, but that's what gives you the "stoplight dance"

Plus how can I find out? I'll convert to coil springs before I fork out for a new valve block only to find that doesn't fix the problem....
let the engine run with the door open for a while, as the compressor runs it'll slowly rise, but not lower down (because of the open door inhibiting the self-leveling). after it's gone up 1/2" or so, shut the door, the compressor will immediately stop and the front will come down. If it does that, your NRV's are leaking.


I will also try swapping around the NRV's in my original block. In theory if one of them is the problem, the sypmtoms should change. Right?!
maybe...

As for the recalibration, I have to say I am a bit confused. At the moment when the vehicle reaches the set height, all corners look right. i.e. both rears are at the same measured height and both fronts are at the same measured heights. Not really sure how that can be improved with a re-cal.
the re-cal just eliminates the calibration as a factor in your issues.

It's also notable that with the compressor electrically disconnected the valve block doesn't seem to make the small up and down adjustments. When connected, the compressor runs, the front end goes up (a bit) and then adjusts down again and so on. I still can't quite figure out how the air is getting past the solenoids, even if an NRV is dodgy.
as above..
 
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