P38A problem with air suspension
- Thread starter GARY88
- Start date
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- Posts
- 58,170
- Location
- Preston Lancs.
Look at the diaphragm valve. Check if air is coming from exhaust outlet when compressor is running. If it is diaphragm is duff.
GARY88
Member
- Posts
- 12
Thank you for that I will try that and give feed back, I have a service kit for the block but cant do much as it`s cats and dogs outside Thank you again for you`r quick respons.
- Posts
- 18,941
- Location
- Buckinghamshire, UK. ('95 DT)
There's an EAS troubleshooting guide by Wammers in the Technical Section. Well worth a read.
GARY88
Member
- Posts
- 12
hi wammers, i have done a complete service with new o rings, new diaphragm, the only wear i could see was in the diaphragm valve there was a split on the underside but not right through but now when the pump pressure hits 39 psi it blows off on the exhaust, do i need to re-calibrate this problem on my diagnostics machine, tia.
GARY88
Member
- Posts
- 12
hi wammers, i have done a complete service with new o rings, new diaphragm, the only wear i could see was in the diaphragm valve there was a split on the underside but not right through but now when the pump pressure hits 39 psi it blows off on the exhaust, do i need to re-calibrate this problem on my diagnostics machine, tia.
- Posts
- 58,170
- Location
- Preston Lancs.
You can't recalibrate that part of the system. You need to explain how you are getting the pressure readings.
GARY88
Member
- Posts
- 12
I'm getting the psi from a pressure guage which i have fitted between the pump and the block on the blue line.
- Posts
- 58,170
- Location
- Preston Lancs.
Oh ok don't really know why you would do that but se la vie. So are you saying the compressor starts up and when the pressure reaches 39 psi it stops and pressure is blown off through the exhaust or are you saying that the compressor starts and at 39 psi air starts to leak out of the exhaust but the compressor keeps running?
- Posts
- 3,235
- Location
- Near Heathrow.
Move the pressure gauge to the tank air-line. Pump really needs checking separately - it's probably worn and might produce 160PSI direct into the gauge, but cant cope with filling the tank. If pump is good, but stops at 39psi & then diaphragm opens exhaust, then maybe pressure switch is bad ?
Your location might help with possible local 2nd pair of hands / eyes / etc. ?
Your location might help with possible local 2nd pair of hands / eyes / etc. ?
GARY88
Member
- Posts
- 12
Hi, its the latter part the compressor starts to leak, I have a feeling that the diaphragm is the problem because it was of a different style, the one that came off had a concave washer in it but the one that came in the kit was a solid rubber, so I have ordered a new one of the sort that came off originally, I have also borrowed a friends block and even though its a little slow it works and i'm getting compression. I should have the new part in a couple of days so I'll let you know if this works.
- Posts
- 18,941
- Location
- Buckinghamshire, UK. ('95 DT)
If the tank is empty then leave a door open with the engine running for 10 minutes and then shut the door and see what happens.
Reading with interest, my p38 is on bumpstops, all 4 orange lights on dash are on.
Jobs done sofar
Changed compressor seals
Checked for leaks in valve block
“1 leak found pipe 3 and stopped leak”
Airdryer leak found,, awaiting to arrive.
Also changed relay under passenger seat
And I also have eas reset buddy that comes up with 2 flashing red light.
I can also jumpstart compressor by removing the yellow relay, using 2 spades 1mm cable,, when I remove them, I hear the puff from exhaust valve.
I have another compressor rebuild kit “ this one with valve sleeve.
And valve block rebuild kit.
Can anybody give advice please
Jobs done sofar
Changed compressor seals
Checked for leaks in valve block
“1 leak found pipe 3 and stopped leak”
Airdryer leak found,, awaiting to arrive.
Also changed relay under passenger seat
And I also have eas reset buddy that comes up with 2 flashing red light.
I can also jumpstart compressor by removing the yellow relay, using 2 spades 1mm cable,, when I remove them, I hear the puff from exhaust valve.
I have another compressor rebuild kit “ this one with valve sleeve.
And valve block rebuild kit.
Can anybody give advice please
- Posts
- 58,170
- Location
- Preston Lancs.
Reading with interest, my p38 is on bumpstops, all 4 orange lights on dash are on.
Jobs done sofar
Changed compressor seals
Checked for leaks in valve block
“1 leak found pipe 3 and stopped leak”
Airdryer leak found,, awaiting to arrive.
Also changed relay under passenger seat
And I also have eas reset buddy that comes up with 2 flashing red light.
I can also jumpstart compressor by removing the yellow relay, using 2 spades 1mm cable,, when I remove them, I hear the puff from exhaust valve.
I have another compressor rebuild kit “ this one with valve sleeve.
And valve block rebuild kit.
Can anybody give advice please
If your compressor is not running without jumping it i would have thought the thermal switch has failed. Get some proper diag like EAS unlock, it is free software but you need an OBDII cable and laptop to run it. Cheapest option for EAS work.
Hi warmers
I used a disc and laptops “ rsw”, just before
1st time it did reach 255
2nd time valve stuck
3rd different again
Come to think it, i got the car in the summer, in about October ish, height started to drop, it did not bother me, coz it raised up
Cheers warmers
I used a disc and laptops “ rsw”, just before
1st time it did reach 255
2nd time valve stuck
3rd different again
Come to think it, i got the car in the summer, in about October ish, height started to drop, it did not bother me, coz it raised up
Cheers warmers
- Posts
- 58,170
- Location
- Preston Lancs.
Can't think you were using it correctly with good idle and green lamp on.
Some like this
- Posts
- 58,170
- Location
- Preston Lancs.
That is bad comms. Where it says no idle should be lit green. Usually caused by serial port adaptor to USB laptop. When using an adaptor you MUST load the driver for into the laptop BEFORE you plug the cable into the USB. Or Windows will load a generic driver that is not suitable for your adaptor.
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