Air Susp Woes - Sags on corner

Hi all,

Well it's only been about 3 months of P38 ownership and i've started with the EAS faults. It had to happen eventually, was kind of hoping not a week before I go on holiday in it but hey thems the breaks !

For the last 2 days, after I turn the car off and walk away, about an hour or so later the rear driver side is right down on the bump stop (almost). Now i'd guess it's leaking and sure enough all bags look a bit old now, never been changed in 10 years it would appear.

But whats puzzling me is that when started up it will rise back up but is then still a few cm lopsided left to right. I'm also puzzled as to why only the back corner drops down - I thought the self levelling would drop all of the corners to match it ? Any ideas please ?

I've just watched all the RSW Solutions vids - great work. Have ordered the EAS lead and a serial to USB converter. About to order 4 new bags, but just niggly worry that maybe a height sensor has gone if it's lopsided ?

Ta, Rick.

Could be a height sensor giving a bad reading, unplug them one at a time (with the tailgate open to freeze the suspension) clean the contacts by spraying with contact cleaner and rapidly plugging and unplugging a few times. It has worked for me. Don't use WD40! Aeroclean 50 or similar from Maplin or CPC is OK.

Thanks Data, good advice. Will nip to maplin now and give that a go.

One of bags is so worn that the outer layer is missing in places. Bizarrely though it has got an obvious leak using the soapy water test yesterday.

Please could you send me your idiots guide to changing the bags ? Think that's a job i'll be doing later this week

Hmm...the bizarreness continues. i drove to the shops earlier took a few minutes to get the kids out and into pushchairs and then walked away from the car. There was a sound of air escaping quickly and the back corner imediately dropped down to bump stop.

I thought that's it then, the bag has finally split. But no, I start it up and after a while it pumps back up. Have been out twice in it since and it's been ok.

Now i'm confused, surely it's either got a leak or it hasn't ?

Deffo got a slow leak anyway, as even a short stop means it has to rise a few cm when I start it back up. Air springs on order....

Kungfu0210 said:

Hmm...the bizarreness continues. i drove to the shops earlier took a few minutes to get the kids out and into pushchairs and then walked away from the car. There was a sound of air escaping quickly and the back corner imediately dropped down to bump stop.

I thought that's it then, the bag has finally split. But no, I start it up and after a while it pumps back up. Have been out twice in it since and it's been ok.

Now i'm confused, surely it's either got a leak or it hasn't ?

Deffo got a slow leak anyway, as even a short stop means it has to rise a few cm when I start it back up. Air springs on order....

Click to expand...

The leaks open and close as the bags fold under, you for sure have a leak, next to go will be the compressor if you don't fix it. All the air bags will be shot so do the lot.

If you want the guide, PM me with an email address

Thanks Data, PM is on it's way.

Good explanation as to why it comes and goes then. I've ordered all four bags so hopefully i'll catch it before the compressor gives up.

Cheers, Rick

Well i bought 4 new bags from Island 4x4 and fitted them last week. It deffo needed doing - see attached photos.

Thanks Datatek for the fitting guide, all went brilliantly. Suspension has been great on holiday for the last week although it does drop slightly overnight. Not sure if it's a leaking joint or just the self levelling doing it's stuff.

Will get out there with the soapy water this week and maybe pull the EAS relay overnight and see if a corner drops.

Pity I can't get usb to serial drivers to work on my Win 7 64bit laptop as i've got the EAS software and diagnostics lead ready to play with !

is it a non branded usb converter? google "unknown device identifier" from huntersoft.

then have a look and see if it can find you a 64bit driver for it.

or you may need to shove a virtual machine on yours to use it. 64bit hads more downfalls than advantages...

Hiya,

It says HL340 on it but I tried their drivers but no luck. You're right, if my lappy hadn't come with 64bit windows pre-installed i'd have stuck with 32bit, it's much easier to get drivers to work. Have also tried Prolific drivers but no joy there either. Will give your suggestion a go now and see what I can find. Thanks.

Hi kungfu0210,

I had the same trouble with a usb emulator on my lap top.
I cured it by getting a serial port pmcia card foe less than a tenner including postage from the states. Works brilliantly no fuss. just type it into googlr or look on RSW web site Storry Wilson was going to post the details of where to get them.

I've just tried the unknown device identifier but unfortunately it doesn't detect the device despite it being shown in device manager with a yellow exclamation mark against it. It comes up in there as "USB2.0-Ser!".

Thanks Wantaquad might try a pcmia card next. Did your card work ok with 64bit as I guess that could be the next hurdle if I buy one of those ?

Thx

:behindsofa:
Despite all the posts relating to EAS not responding as quick as people wish, can I suggest that the first port of call is the condition/performance of the compressor seal. This is the primary item in the system what dies. Price and time wise, surely its the first obvious thing that should be checked..it's low cost and easy to rreplace. Ok, you may have an obvious leak from an air spring, but usually they deteriorate over a period of time.
Let's get to basics....the system needs a good air supply to operate...the compressor. The heights are controlled by feedback from the four height sensors (One on each corner) which in turn via the ECU, open and close solenoid valves to either inflate or deflate each spring to give a height within certain limits. We are not looking at "Thou's" we're looking somewhere in the
region of +/- 7mm on a flat surface
Unless the springs are absolutely shot, mine were cracked etc.and were the originals..over 10 years old..the chances of a "Blow out" is remote.
Most of the posts on here relate to "Suspension slow to rise etc." which indicates poor compressor performance= worn piston seal.
It is vitally important that the compressor is delivering the pressure & volume bfore going off on a wild Goose chase.
My P38 is 13 years old, I have replaced the springs and the compressor seals once in that time and have never had an EAS fault displayed. It's a good system..far better than coil springs. Read up about how the system works and get your head around it...It's straight forward and not the"Monster" that people think or believe from hearsay

Fair and justified comment, but probably not the compressor seal causing mine to drop height overnight.

As an aside, I am planning to refurb the seal anyway as I'd guess it had a hard time of it recently with my leaky bags. You're right, I also think the EAS is a great system when it's working, and regular preventative maintenance should hopefully keep it going strong.

Even if all is working correctly, they will drop ovenight if parked on uneven ground.

Kungfu0210 said:

Fair and justified comment, but probably not the compressor seal causing mine to drop height overnight.

As an aside, I am planning to refurb the seal anyway as I'd guess it had a hard time of it recently with my leaky bags. You're right, I also think the EAS is a great system when it's working, and regular preventative maintenance should hopefully keep it going strong.

Click to expand...

Correct, the compressor seal has nothing to do with losing overnight. But what Irish says is correct. The compressor and it's associated items have but one purpose in life, and that is to provide air pressure. If you have good pressure, that is all you need to know about the compressor circuit. Any other problem is from the valve block onwards.