[Parkheadlad]

Recently purchased a P38 4.6 Vogue Yr 2000 and replaced the compresser a couple of weeks ago (previous one was dead). The compresser seems to switch on and off on a regular basis and concerned it will burn itself out. I had a local garage to check it out and found no leaks with the air springs or components leading to and from the reservoir tank. Mechanic said it could be the valves located in the EAS unit in the engine. Had a look at it tonight and the compressor is warm/hot to touch. Is there anything to worry about?
No problem with the height of the RR.
Any thoughts would be most welcome.

 

[wammers]

Don't believe him you have a leak somewhere.

 

[dogsbody]

The compressor is triggered by a pressure switch under the valve block. If this is a bit over sensitive then it could be triggering the compressor at the slightest pressure drop. Mind you, it still means that you're losing air somewhere!!

 

[Datatek]

Airbags leaking if they are more than 7/8 years old, otherwise diaphragm in the valve block leaking. Remover the exhaust filter lower rear corner of the EAS box and see if there is air coming out.

 

[Parkheadlad]

Thanks for the advice. The mechanic said the air springs are all in good condition which was good news to me. I am new to P38s and not much of a DIY person but cant afford to visit a garage again this month as I have already forked out nearly £500 to 'fix' the compressor problem and a week later an air mass flow meter had to be replaced (including labour). I want to be more 'pro-active' in looking after my P38 which I am really enjoying despite the initial out lay of repair fixes.
Is it relatively easy to check if the diaphragm in the valve block is leaking (Datatec) and whether the pressure switch is over sensitive (dogsdody).
Is it easy to do the 'soapy' water test under the RR (which the mechanic said he did) without raising the RR - is there a walkthrough which would guide me?
Great forum, great advice as always.

 

[Datatek]

Thanks for the advice. The mechanic said the air springs are all in good condition which was good news to me. I am new to P38s and not much of a DIY person but cant afford to visit a garage again this month as I have already forked out nearly £500 to 'fix' the compressor problem and a week later an air mass flow meter had to be replaced (including labour). I want to be more 'pro-active' in looking after my P38 which I am really enjoying despite the initial out lay of repair fixes.
Is it relatively easy to check if the diaphragm in the valve block is leaking (Datatec) and whether the pressure switch is over sensitive (dogsdody).
Is it easy to do the 'soapy' water test under the RR (which the mechanic said he did) without raising the RR - is there a walkthrough which would guide me?
Great forum, great advice as always.

It's unlikely to be the pressure switch. I told you how to check the diaphragm.
As for the airbags, if they are original, it's highly likely they are leaking, look at them for signs of perishing/crazing/small splits, it's not always possible to see the leaks with soapy water as the leaks can be in the folded under part. It is worth doing the soapy water check on all the pipes where they go into the airbags and the valve block etc

 

[Parkheadlad]

I sprayed all the areas of the valve blocks with soapy water and when the compressor stops it lets out a whoosing noise - this sprayed the soapy water everywhere from one of the corners. Is this normal - is this connected to the the exhaust filter (Datatek)? Sorry, I am only a beginner.

 

[wammers]

I sprayed all the areas of the valve blocks with soapy water and when the compressor stops it lets out a whoosing noise - this sprayed the soapy water everywhere from one of the corners. Is this normal - is this connected to the the exhaust filter (Datatek)? Sorry, I am only a beginner.

That is air being exhausted after compressor stops. The gallery is needed for releasing air from bags. Follow the steps in the "How To" section at the top of the page. Then get back and tell us what you have found.

 

[p3bbillym]

Had exactly the same problem as you a month or so ago. Changed the front airbags as they were cracked and worn, refurbed the valve block and the compressor which didnt cure the problem. Rear airbags looked perfect so carried out leak test with proper leak tester and no leaks were evident. Finally bit the bullet and replaced the rear bags which cured my problem. On inspection of the old bags found they were cracked and de-laminated where they folded over themselves.

 

[Parkheadlad]

Checked for myself the air springs - they are in good condition - soapy water test did not reveal any leaks. Did the soapy water on the valve block and again no sign of any leaks. When stationary I can hear the compressor - in most conditions usually switched on, cuts out for a few seconds and then switches back on.... Very annoying! The compressor is hot to touch when I check after a journey. Looks like a Valve refurb - just dont have the time at the moment and spent too much on the RR since I bought it a couple of months ago to have a mechanic working on it.

 

[wammers]

Does knowbody ever bother to read the "How to" section?

 

[Datatek]

Checked for myself the air springs - they are in good condition - soapy water test did not reveal any leaks. Did the soapy water on the valve block and again no sign of any leaks. When stationary I can hear the compressor - in most conditions usually switched on, cuts out for a few seconds and then switches back on.... Very annoying! The compressor is hot to touch when I check after a journey. Looks like a Valve refurb - just dont have the time at the moment and spent too much on the RR since I bought it a couple of months ago to have a mechanic working on it.

I'd still put money on it being the airbags

 

[Datatek]

Does knowbody ever bother to read the "How to" section?

Most don't even seem to have noticed it's existance

 

[Parkheadlad]

First of all thanks to Datatek for providing me with the all important EAS cable and software. Did the initial simple checks as suggested by Wammers but all ok. She stays rock solid overnight in terms of height.
I have attached the fault readings from the cable and the software programme - the problem is where do I start/ are some of them old fault readings etc. Help would be much appreciated.

 

[JohnP38]

First of all thanks to Datatek for providing me with the all important EAS cable and software. Did the initial simple checks as suggested by Wammers but all ok. She stays rock solid overnight in terms of height.
I have attached the fault readings from the cable and the software programme - the problem is where do I start/ are some of them old fault readings etc. Help would be much appreciated.

The attached says you dont have a good idle.Ie green .
Those faults are probably from bad comms.
You must have a good idle to read the stored faults.
First after obtaining a good idle,clear all faults ,disconnect as per procedure and then drive RR around for a while and then read codes again and see what codes have been relogged.

 

[Datatek]

First of all thanks to Datatek for providing me with the all important EAS cable and software. Did the initial simple checks as suggested by Wammers but all ok. She stays rock solid overnight in terms of height.
I have attached the fault readings from the cable and the software programme - the problem is where do I start/ are some of them old fault readings etc. Help would be much appreciated.

That means you have not established communication (and haven't read the instructions LOL) "Status = button" has to go green and say "Good Idle". Either you have a problem with your USB to serial adaptor or corrosion in the OBD socket.