Hi All,
Wonder if anyone may have some pointers: For a while, the car suspension has been "leaking" air on the rear, very slowly. Looks like RH side rear. Symptom is the car sits very low after being parked for a while, and the compressor working more than it should (say, running every 5-10 minutes).
Bentley dealer inspected and told me its one or both air suspension units being leaky, and needing changing. Agreed the RH side unit was the suspect since the car "sunk lower, or led" on the RHS, with the LH side evidently catching up (via self-levelling?).. So, bought a air susp unit from Bentley UK (only $2,000 and change ). Car is in Spain at moment and Bentley here refused to change it (citing warranty etc but clearly wanting to sell their own far more overpriced part). Used a v. experienced indy and changed the RH unit (incredibly expensive new original part). Shock horror - no change! Seems I had changed a perfectly good unit, and the leak must be somewhere else. But where?

Any pointers much appreciated..

Adds to my issue with the driver seat that refuses to move forward..

 

Monday Feb 13 2017 3pm San Francisco...what is year, model and mileage on car. Are you original owner...how long have you had car...when you say very expensive new original part could you please clarify....sorry that after you going through all the time and expense, the diagnosis apparently was not correct....hope with more info and help of our resident experts we can nail it down...JimB

 

Thanks Jim,
The car is a 2006 GT with about 55,000 miles on the clock. UK (RHD) car. I am the second owner and bought the car two years old in 2008.Currently the car is in south of Spain.
The air suspension unit was expensive, is all I'm saying. The official dealer here (who also deals in Ferrari, Maserati, Range Rover) quoted $2,500 for each air suspension unit after inspecting and insisting that one unit had developed a leak "because they had seen that before".. Well I bought the rear right hand unit from Bentley UK (HR Owen) somewhat less dearly, and took it to Spain. Had it changed at a highly recommended indy who does a lot of work on Bentley, Lamourghini, Ferrari etc..lots of those around here too..), after the local dealer refused to touch it unless I bought the overpriced part from them. All I really know is that, following the change (I kept the old air susp unit - they can be refurbished at least in UK), there is zero change and the symptoms are exactly the same.
Those symptoms are that, once car is stopped it will sink too low (gradually), leading the way on the right hand rear side (leave it for a few days and the rear wing wheel arch will be level with top of the wheel/tyre). And, when car is running the compressor has to work too often to lift the rear of the car. So there is apparently a leak somewhere..but unless the brand new original air suspension unit has exactly the same leak as the 10 year old one, it is not the unit itself... So my Q is really, where else could such a leak be? Are there any "usual suspects".. I am no expert, but not entirely useless with a car either. That said, I don't; have my tools and garage set-up down here..
Eagerly awaiting.. Thanks!

 

....the answer to your immediate problem is this....Look it up on this site...just type in "air suspension leaks" Like I just did and you will probably find your answer...The logic behind this is apparent....There are very knowledgeable experienced people here whose time is valuable and freely help and give their time...but they should not be expected to stop what they are doing every time some novice like myself asks a question...Thanks JimB

 

Well... J JJ's posting, as always, is very helpful. I guess my point was whether anyone had come across the issue and it was something other than the air suspension unit itself..And surely I didn't ask anyone to drop everything and rush to answer, again, my stupid question..
But often the problem with many threads is this; people ask for help and pointers, then (it is assumed) solves the problem, but then forget to complete the thread with what the problem was. Some experts are incredibly good and extremely helpful, and to others it would always be helpful to finish the feedback on problem solved and what solved it..
Many thanks for all the aggregate know-how which is most helpful.
Based on the Panamera example and the Flying Spur issue it seems to me that the valve block or the air line must be the culprit. I will try to get to these with some soapy water and see what can be gleaned.. Meanwhile, anyone with better ideas please feel free..

 

Update.. SO as before I had gone to the dealer in Spain who told me new air susp units were required $2,200 plus work please..bought the rear right one from Bentley UK a fair bit cheaper and had it changed...No cure!!
So I've Just had 4 hours diagnostic done at same place but mainly re my driver seat issue (why don't ask) and they have determined that the air pipe and connectors need changing on the right rear. Is this a big or difficult job?
Lesson 1: Should have tried the soapy water spray first, and possibly save a bundle. At least I have a brand new air susp unit..

 

....Hello Lars from San Francisco....First let me say up front, I know less about this situation than you do, but I have read most discussions here on the general subject....starting with the fact we are dealing with a 2006 CGT, a model and year notorious for vacuum leaks...but vacuum I believe is not relevant here....as you stated, it is only remote possibility that both your old unit and your replacement unit had a bad seal or leak...that would seem to leave two areas of possibility, one, a leak in the plumbing somewhere, or two, an electric computer device breakdown...Here is where we need Johnny's expertise or ZaOs or Steven...these guys know this stuff in and out, so hopefully they will be tuned in....JimB

 

Thanks Jim, Yes well the dealer did 4 hours diagnostic on this issue and my driver's seat and determined it is a faulty air line and/or connectors on the right hand rear side. Hopefully solves the problem.. Moral of the story, get under it and spray some soapy water... Johnny posted a good picture of the area on a different thread same topic.

 

Having pondered / researched this a bit further I'm left with a question or two...recap first.. car sagging on right rear, I have replaced with original Bentley Air unit on that side, no cure. After further diagnostic dealer says replace RightRear Air line and 4 connectors (!).. Questions:
1. Why 4 connectors for one line, surely one line has two ends and need two connectors?
2. As shown in Johnnny's pictures the airline runs in the wire harness and should be somewhat protected..I have not found any trace of the actual airline being faulty in any thread I've seen on AudiWorld D3 Audi A8/S8 or on Bentley. Anyone know if air line is likely to leak, or should I do a step-by-step, doing the connectors first?
3. Connectors should be a straightforward DIY job, but what about the air line? It will be the shortest one being from the spare wheel well to the rear strut unit .. Bentley indicate 2.9 hours but that is surely to tidy everything inside the wiring assembly, or no?

Finally, although the original air susp unit was probably fine, I'm inclinde to leave the new one on the car and keep the old original one as spare. Or would you return the new one for a refund - which is uncertain 3.5 months from purchase and having been fitted on the car (only 10 miles though)..

Thanks as always..

 

Hello Lars,
I believe you are in Spain, so it's about 10:50 PM for you if you see this immediately , you can PM me your number if you want and I will call you , I have some comments and questions on your two issues at the moment on the two threads, or I can just post them in both, but most times its best person to person over the phone to get the clearest understanding.


Okay, now to your question of why 4 connectors, Yes as you stated and seen in my pictures, all the air lines for front and rear suspension are interwoven into the wiring harness, so what the dealer is most likely doing is splicing the line in the wheel well area, that's 2 connectors, and doing the same on the underside of the vehicle to get to the compressor, that's 2 more connectors, for the total of 4, and I must say that is one hell of a jerry rig, believe me, if I ever had a line go bad you I would be fishing the new line along side the harness and cloth taping them together, or running a tube along side the harness and the fish the new line through said tube, then adding the connectors on each end for a total of 2, the only areas of somewhat protection needed are in the trunk area if needed at all, as they are just taped in cloth from the factory, and once the air lines exit the trunk (boot) to either the wheel well or under the vehicle to the compressor, they are just the lines, no protection, no tape...
I was going to paste a link to AW where Louis changed out the air bag portion of the strut assembly, and found that it may not have been the air spring bag itself, but the larger o-ring at the bottom where the air spring and strut seal against each other, BUT you replaced with a factory new unit, so I am discounting that as the cause, SO that leaves either the air line failing, the valve block unit failing, or is it possible that the right rear height sensor is defective or disconnected, as when one side can not achieve proper height, the rest of the strut compensate to achieve a certain level.


Now as you have found, I have never seen an air line fail, unless it was just a loose connection at either end, and then a little tightening solved that, or someone damaged the air line at the strut while working in the area, I think the only other times was back in the day on my 77-82 Fleetwood Brougham's that had the black plastic air line to close to the exhaust....


Just in case someone wanted to see the AW thread.


http://www.audiworld.com/forums/a8-s...rider-2913592/


.

 

Thanks v helpful. I PM'd my details.
the leak as I recalled developed gradually,a nd without any work having been carried out in the area at a time close to that.
A tech at Bentley UK advised that there is a easier fix should the air pipe have a leak. One can just cut out the relevant section and join up with a "fix&lock" pipe repair unit rather than replacing the entire line (most work to replace would be to pull the line inside the wiring assembly in a tidy manner). Assuming one can actually find the leak, which isn;t always easy..
Will update depending on whether we're able to hook up on phone..

 

....Hello Lars...how many different dealerships or mechanics have you seen recently regarding both seat issue and air situation...imagine it is disconcerting to have to use expensive process of elimination...one good mechanic probably could have diagnosed and fixed all in an afternoon...JimB

 

Hi Jim,

You would have thought so.. The Bentley dealer here in south spain inspected the car a while back and told me it was definitely the air susp unit. Wanted $4,400 for the pair, plus labour. So I bought the one side sagging from Bentley UK for a fair bit less and had an indy fit it. Which fixed absolutely nothing, since that wasn't the problem.
Also tried new parts for the seat namely green relay and control panel on the side of seat. Again no luck, but Bentley UK will take those parts in return. However, when said indy was too busy to do the diagnostic, I took it back to the dealer again, getting weary of trial and error wit expensive parts. Now they claim to have done proper diagnostic (hmmm) and identified the control module on the seat and the air line and/or connectors on the RHRear as the guilty parts.
So I tried diagnostic, by dealer (head tech actually), only he turned out to be guessing since the unit is the more normal culprit. Which is a big reason why I won't do the hugely overpriced repair too with them. Didn't even offer an apology for messing up the air suspension unit mis-diagnostic.. So the question is, where do you find a good mechanic... Also, air leaks are not easy to pin down always, as many threads can bear witness to both here and on AudiWorld etc..

 

Update: Got the car back from the dealer. They explain that there is a clear leak to the air line and/or connector at the end close to the air strut unit. It is actually audible, so how they missed it and instead diagnosed the need for new air suspension units earlier is extremely poor (wanted to charge $5,000 + for the pair)..As it turns out, just a guess based on the most common (and hugely expensive) fault.
I am requesting the repair parts from Bentley UK, the techs there explained they have a repair part that allows to cut out only the damaged section of the air line rather than change the entire line. How the line could have been damaged I don;t know, but it has little protection above the wheel except for the partial protection of the inner wheel arch lining. To be continued..

 

Sounds like the mechanics in Spain are as ineffectual as the ones in NW England.
Good luck.

Les.