Another EAS problem!

Hi All,

I bought a P38 about a year ago, an X reg (2000) 4.6.

I’ve sorted a few niggles with her over the year, but after a number of occasions being a bit slow to come up in the mornings and an unsightly trip back from work on the back of an AA lorry, I thought I’d better give the EAS system a bit of an overhaul.

So, 4 Arnott G2 bags, a new compressor and a rebuilt valve block with new o-rings and diaphragm and a lighter wallet later……

The good news is I’m fairly certain that I have no leaks, and a lot of soapy water agrees J

But, she won’t come up level at all. At random intervals, she’ll come up on the left, or the right, or the front, or the back (less often). I’ve only managed to get her up level once, at high profile, where she stayed over a long weekend while I was away (she was supposed to come too, but not in this state L ). She’ll also try (according to the faultmate) to regularly go into extended profile, but she’s certainly not got the chassis stuck on anything!

Most of the time the lights are flashing to show moving between heights, but she’ll also show that she thinks she’s at standard profile, despite the fact she’s sitting at about a 35o angle!

There are no faults in the system, so I don’t think it’s the height sensors.

I suspect its something daft I’ve done putting the valve block back together. I’ve read that its good to use plenty of silicone lube when fitting the new o-rings, to reduce the chances of leaks, so I did on all but the NRVs. Is this correct? Or can it be overdone?

I shall try stripping the valve block again at the weekend, just to make sure I haven’t got an un-seated ring (!) but I would’ve thought that I’d be getting either leaks, or fault codes relating to stuck valves.

Has anyone else had a similar issue, or can you give me any pointers what I might try?

Thanks

Marc

:welcome2:

Good write up....

It is possible that the Valve Block Diaphram valve seals are installed upside down - it is easy to do apparently as it isn't obvious which way up they are supposed to go - Wammers or Datatek will confirm correct orientation...

Check for leaks from the exhaust port - remove the muffler and place your hand over the end to check for a small release of air, could be one of the NRV's isn't seating.

If the valve block checks out and the compressor is strong, no leaks etc.....assume a dodgy Driver Pack - sometimes these fault but it doesn't show up on diagnostics.

The rear should always rise first then the front. Did you put the solenoids back in their correct positions?

Cheers Guys,
I had read about the possibility of the driver pack giving up, is this normal after replacing the other parts, or just coincidental? Is there a way of testing it without another vehicle?

I numbered the solenoids before taking them off, following the step by step on paulsp38.com. But, I'm not 100% sure I got the orientation of the actual valves as they were originally, would that make a difference?

Equally, if there is a right and wrong way up for the diaphragm, I couldn't say for certain that I've got that right (50/50 chance though!!).

Cheers
Marc

You need to stick it on some diagnostics to see what's going on sounds all screwed up to me. All the coils have to go back where they came form. The four middle valves can be interchanged but exhaust valve and inlet valve have go back where they came from. Diaphragm only fits one way open side out. Flat side in. Rear should always go up first followed by front. If it's going up any other way either you have something in the wrong place coil wise or some bad sensors or sensor connections. Driver pack is a possible, no check that i know of other than fitting a known good unit.

I've got it on a faultmate MSV2 extreme, but its not showing (that I can identify) any faults or issues.
The coils definitely went back into the solenoids they came out of, just not sure of the exact position of them (as in north/south/east/west orienation). I double checked the valves against the diagram on paulsp38.
I'll double check everything over the weekend, as well as some contact cleaner on the connections.
Although I was careful not to overextend the height sensors while I was moving the axle about getting the new bags in, could there be a problem with a sensor that doesn't trigger a fault code?

marcinbrighton said:

I've got it on a faultmate MSV2 extreme, but its not showing (that I can identify) any faults or issues.
The coils definitely went back into the solenoids they came out of, just not sure of the exact position of them (as in north/south/east/west orienation). I double checked the valves against the diagram on paulsp38.
I'll double check everything over the weekend, as well as some contact cleaner on the connections.
Although I was careful not to overextend the height sensors while I was moving the axle about getting the new bags in, could there be a problem with a sensor that doesn't trigger a fault code?

Click to expand...

Lots of silicone on all the "O" rings could be the clue.
When the car is at an angle, you need to read the actual sensor readings to see if they are sensible. Not sure how to do that on the Faultmate as I don't have that software module, I use the EAS suite from RSW
A duff sensor will not always show up as a fault.

If the shocks are good, you cannot over extend the height sensors, but you can move the wiper to an unused part of the track where it picks up crud and upsets the resistance reading. Should have followed my guide.

OK, Finally managed to get to having another look this evening. Sadly no fix, here's what I've done:

Taken the valve block apart again to make sure no unseated o-rings and wiped off any excess silicone lube. Double checked to make sure correct valves in correct solenoids.

Dropped her onto blocks (in place of bump stops) for 105mm rear and 100mm front. Checked the height readings and all seemed sensible, within reason of the stored target height for standard profile.

Jacked back up onto stands and checked height readings again, all had moved up as on higher stands than the block. So height sensors seem to be OK.

I haven't checked the resistance of the height sensors, as given the above I didn't want to disturb them unecessarily.

When I have put it all back together, each corner has come up, just not together, or at anything resembling level. I did at one point have her level, but then moving height soon sorted that out, dropping one side only.

At one point (I had to laugh or cry) I was standing there watching her literally dance . Sadly she finally settled up at the rear and down at the front, with the front left being the lowest of all

Is all this now symptomatic of a failed driver? I'm not sure what to try next.

Cheers

Marc

Try parting and cleaning the connectors in the EAS box. Then as I said before, read the heights when it is sitting at an angle. Maybe as you have had the valve block out you have the airlines back in the wrong holes. Equally there may be a significant leak.

Hiya,

Datatek said:

Try parting and cleaning the connectors in the EAS box.

Click to expand...

Do you mean by that the EAS box in the engine bay, so the connectors for the valve block (and driver pack) and compressor? If so, i did spray these with contact cleaner and checked for any bent/broken pins. All seemed fine.

The height sensors when she's sat at an angle do read that she is at an angle. They appear to have sensible values no matter what I do (i.e jacking, stands, blocks or just sitting on her bags. She does still sometimes think shes reached the correct height though (solid light on dashboard switch, but takes a loooong time to get there), even when visibly at an angle. Height sensors still read that one side is higher than the other though.

marcinbrighton said:

Hiya,



Do you mean by that the EAS box in the engine bay, so the connectors for the valve block (and driver pack) and compressor? If so, i did spray these with contact cleaner and checked for any bent/broken pins. All seemed fine.

The height sensors when she's sat at an angle do read that she is at an angle. They appear to have sensible values no matter what I do (i.e jacking, stands, blocks or just sitting on her bags. She does still sometimes think shes reached the correct height though (solid light on dashboard switch, but takes a loooong time to get there), even when visibly at an angle. Height sensors still read that one side is higher than the other though.

Click to expand...

That suggests you have an air leak. The ECU will give up if the time to raise and level is too long.

any idea where to look though, if I've done a soapy water test at all available points and it isn't showing any issue? She'll stay up for a number of days too

marcinbrighton said:

any idea where to look though, if I've done a soapy water test at all available points and it isn't showing any issue? She'll stay up for a number of days too

Click to expand...

If it's slow to rise and/or fails to rise evenly, then there has to be either a failure of air pressure being directed to the slow corner or the air pressure is escaping, always assuming the compressor is producing sufficient pressure & volume.
Airsprings can leak up inside the fold at the bottom and you will never see it with soapy water.

On the EAS air pressure is king, without it all the other parts are a waste of time.

the problem is, there isn't one slow corner. any or all of them will come up, and stay up overnight with no issue. The compressor is new, and appears to be pulling in air quite happily.

It is also switching off the compressor OK. Thermal switch continues to say normal (the old compressor was reading hot and switching off, which was the main reason I put a new comp. on there.

I agree, it feels like a lack of pressure, but I just don't get why.

At the moment she's sitting with her a*se in the air, bags fully extended, and no movement since last night. I'd assume that if its a bad enough leak to not bring it up properly it would be bad enough to drop overnight.

I know just having new parts doesn't necessarily mean they are OK, but from what i can see / check of the air bags and compressor they seem to be alright.

I'm going to try opening the valves individually with the Faultmate this evening, to see if I can hear or feel them moving (is this likely??) and I'll report back.

Cheers for your help and advice on this guys, I have to confess its starting to get a bit frustrating as it just doesn't seem logical at the moment

marc

marcinbrighton said:

the problem is, there isn't one slow corner. any or all of them will come up, and stay up overnight with no issue. The compressor is new, and appears to be pulling in air quite happily.

It is also switching off the compressor OK. Thermal switch continues to say normal (the old compressor was reading hot and switching off, which was the main reason I put a new comp. on there.

I agree, it feels like a lack of pressure, but I just don't get why.

At the moment she's sitting with her a*se in the air, bags fully extended, and no movement since last night. I'd assume that if its a bad enough leak to not bring it up properly it would be bad enough to drop overnight.

I know just having new parts doesn't necessarily mean they are OK, but from what i can see / check of the air bags and compressor they seem to be alright.

I'm going to try opening the valves individually with the Faultmate this evening, to see if I can hear or feel them moving (is this likely??) and I'll report back.

Cheers for your help and advice on this guys, I have to confess its starting to get a bit frustrating as it just doesn't seem logical at the moment

marc

Click to expand...

Overnight the EAS should wake up every six hours and drop the suspension to match the lowest corner. You may have a sensor or sensors that is/are showing the same reading in several different positions.

hmmm, good point, but definitely not dropping! time to try swapping the height sensor's one side to the other? (will have to wait til thursday to do this, as my trolley jack has finally given up the ghost as well (never rains....eh?) and new one being delivered on thurs.

I've just tried the valves, each one is clicking when I open it through the software, but although I felt a small upward movement in the front left (when I opened the inlet valve?) as I was leaning into the bonnet, none of the other corners moved. nothing moved when I opened the exhaust valve either.

Gonna have to drive it soon though, just to go and put some fuel in her

Will it be ok to drive (carefully) with the suspension all over the place?

wammers said:

Overnight the EAS should wake up every six hours and drop the suspension to match the lowest corner. You may have a sensor or sensors that is/are showing the same reading in several different positions.

Click to expand...

Concur - sounds like iffy sensor readings!!

You should be able to feel the Solenoid 'click' as it activates, as this is the valve stem lifting...can be heard too at times....

marcinbrighton said:

hmmm, good point, but definitely not dropping! time to try swapping the height sensor's one side to the other? (will have to wait til thursday to do this, as my trolley jack has finally given up the ghost as well (never rains....eh?) and new one being delivered on thurs.

I've just tried the valves, each one is clicking when I open it through the software, but although I felt a small upward movement in the front left (when I opened the inlet valve?) as I was leaning into the bonnet, none of the other corners moved. nothing moved when I opened the exhaust valve either.

Gonna have to drive it soon though, just to go and put some fuel in her

Will it be ok to drive (carefully) with the suspension all over the place?

Click to expand...

Depends on year I think...early ones were handed later ones not (IIRC)

Nothing will happen when you open the exhaust as you will have to open a corner too...the system opens the corner valves and the exhaust to lower, and opens the inlet and the corners to fill....just opening and closing the exhaust won't do anything!!

As for driving - the Plod got take a dim view of it!!!

This is what she's looking like at the moment, been like that for 24 hours now.