AudiWorld Forums

AudiWorld Forums (https://www.audiworld.com/forums/)
-   A8 / S8 (D3 Platform) Discussion (https://www.audiworld.com/forums/a8-s8-d3-platform-discussion-60/)
-   -   07 A8 Rear Air Suspension Issues after Jacking (https://www.audiworld.com/forums/a8-s8-d3-platform-discussion-60/07-a8-rear-air-suspension-issues-after-jacking-2964558/)

pelletman 12-26-2018 06:17 AM

07 A8 Rear Air Suspension Issues after Jacking
 
Hello all

I jacked up the left rear wheel to repair a flat and when I let it back down the rear suspension (both sides) were bottomed. Car has about 160K miles. The fronts seem to be fine. I jacked on the jacking point under the rear left door, and I was NOT in jack mode. I understand how the system works, I have read a bunch of threads on the subject. I have jacked the car up from the rear diff and have her on jack stands, have the left rear inner fender liner removed as I thought maybe somehow I had pinched a line or something. It doesn't look like that is the case. I run the car and I can't hear any obvious leaks, but the rear doesn't pump up. I will post the VCDS scans later as they are not in the computer I am on at the moment. Has anyone had a similar issue? I am basically wondering where to start first. Every once in a while I would see the yellow and green lights prior to this. My thoughts are to soap up the connections at the rear left shock and anything else I can get to there, and if I don't find anything maybe start at the compressor, check output, go to the distribution block and check there, then I guess go to the right rear.

Has anyone tired to air these up under water to check for leaks? It would seem to me that would be an effective way to test the actual shock and find leaks easily.

Any input you may have would be appreciated.

Giovanni Giovino 6.0+6.0TT 12-26-2018 07:48 AM

Hello Pelletman,
If you could clear up one thing for me, you say you jacked it up by the rear diff and have it on jack stands, where are the jack stands, is the rear hanging ?
Did you check level sensor rods ?


Originally Posted by pelletman (Post 25253154)
Hello all

I jacked up the left rear wheel to repair a flat and when I let it back down the rear suspension (both sides) were bottomed. Car has about 160K miles. The fronts seem to be fine. I jacked on the jacking point under the rear left door, and I was NOT in jack mode. I understand how the system works, I have read a bunch of threads on the subject. I have jacked the car up from the rear diff and have her on jack stands, have the left rear inner fender liner removed as I thought maybe somehow I had pinched a line or something. It doesn't look like that is the case. I run the car and I can't hear any obvious leaks, but the rear doesn't pump up. I will post the VCDS scans later as they are not in the computer I am on at the moment. Has anyone had a similar issue? I am basically wondering where to start first. Every once in a while I would see the yellow and green lights prior to this. My thoughts are to soap up the connections at the rear left shock and anything else I can get to there, and if I don't find anything maybe start at the compressor, check output, go to the distribution block and check there, then I guess go to the right rear.

Has anyone tired to air these up under water to check for leaks? It would seem to me that would be an effective way to test the actual shock and find leaks easily.

Any input you may have would be appreciated.


MP4.2+6.0 12-26-2018 08:13 AM

My question--and likely suggestion--is whether after you let it off the jack you really gave it a chance to pump back up again? As in, start car, let it run for a bit, etc. Check battery if need be. IIRC, the power management system does cut out the compressor if it decides battery is not up to snuff, so maybe you are just fighting that? Starting it up would usually get my compressor going after a minute or so regardless.

Besides just giving it a decent chance to work, make sure rear suspension sensors did not get dislodged somehow.

I jacked mine up at the rear diff a fair number of times. I certainly forgot to put it in jack mode more than a few times on the various corners/ends, so neither of those are catastrophic issues by themselves.

Dalplex 12-26-2018 02:50 PM

It is not causal.

pelletman 12-26-2018 05:17 PM


Originally Posted by Giovanni Giovino 6.0+6.0TT (Post 25253181)
Hello Pelletman,
If you could clear up one thing for me, you say you jacked it up by the rear diff and have it on jack stands, where are the jack stands, is the rear hanging ?
Did you check level sensor rods ?

When it happened it was just jacked up on the rear left corner with the jack under the rear left (driver's side) door on the jacking pad to pull off the tire to fix it. When I let it down the suspension had sunk. Presently (like a month later) it is up in the air and I had jacked it up on the rear diff and put jackstands near where the rear control arm meets the differential. I believe the rear wheels are now hanging. I have not checked the level sensors, how would I check them?

pelletman 12-26-2018 05:25 PM


Originally Posted by MP4.2+6.0 (Post 25253199)
My question--and likely suggestion--is whether after you let it off the jack you really gave it a chance to pump back up again? As in, start car, let it run for a bit, etc. Check battery if need be. IIRC, the power management system does cut out the compressor if it decides battery is not up to snuff, so maybe you are just fighting that? Starting it up would usually get my compressor going after a minute or so regardless.

Besides just giving it a decent chance to work, make sure rear suspension sensors did not get dislodged somehow.

I jacked mine up at the rear diff a fair number of times. I certainly forgot to put it in jack mode more than a few times on the various corners/ends, so neither of those are catastrophic issues by themselves.

It had plenty of time to pump up. Probably sat there running for 30 mins. Battery has always been fine. I didn't think just jacking it would cause the problem. I'll check the sensors next time I am with the car. Thanks for the input!

Giovanni Giovino 6.0+6.0TT 12-27-2018 06:50 AM


Originally Posted by pelletman (Post 25253380)
When it happened it was just jacked up on the rear left corner with the jack under the rear left (driver's side) door on the jacking pad to pull off the tire to fix it. When I let it down the suspension had sunk. Presently (like a month later) it is up in the air and I had jacked it up on the rear diff and put jackstands near where the rear control arm meets the differential. I believe the rear wheels are now hanging. I have not checked the level sensors, how would I check them?

If the rear is "hanging" it will not pump up the rear air struts at all, it is actually releasing the air in the rear struts because the sensors are showing the rear to be to high.

pelletman 12-27-2018 07:19 AM


Originally Posted by Giovanni Giovino 6.0+6.0TT (Post 25253553)
If the rear is "hanging" it will not pump up the rear air struts at all, it is actually releasing the air in the rear struts because the sensors are showing the rear to be to high.

Ahhhh, THAT'S good to know! Lol. I will move the stands under the lower control arms and see what happens after I check the level sensors...

pelletman 12-28-2018 10:41 AM

OK, moved the jackstands so the weight of the car was on the suspension, still under control arms, closer to the tires. Susp lights went out on dash. Put the tire back on, put the car on ground, rear tires are 3" up on blocks so I could get jack under, green and yellow lights are back on. Suspension is low in rear. I can't hear any leaks. I scan with VCDS and I don't see anything for suspension issues. I assume they would show up in group 34 but i get all is good. LEvel sensors looked good but that is just visually. I am confused! Pics are from before I moved jack stands. Thanks for your help!

https://photos.app.goo.gl/dmJ8Tu1TwaXf72Ea8

pelletman 12-28-2018 10:49 AM

The MMS allowed me to try to put it in lift mode, all the options were there. I did, the compressor ran for a minute or so, then shut off. The rear didn't pump up at all and I am not sure the front moved at all. A code did show up

Friday,28,December,2018,14:45:21:24716
VCDS Version: Release 18.9.0 (x64) Running on Windows 10 x64
Ross-Tech: Home

Address 34: Level Control Labels: 4E0-910-553.clb
Control Module Part Number: 4E0 910 553 H HW: 4E0 907 553 F
Component and/or Version: LUFTFDR.-CDC H06 4480
Software Coding: 0019911
Work Shop Code: WSC 11111 111 45799
VCID: 2809043BDEF51387F6B-807C
1 Fault Found:

01400 - Suspension Level Control
002 - Lower Limit Exceeded
Freeze Frame:
Fault Status: 11100010
Fault Priority: 2
Fault Frequency: 1
Reset counter: 78
Mileage: 259846 km
Time Indication: 0
Date: 2018.12.22
Time: 19:00:01



All times are GMT -8. The time now is 08:53 PM.


© 2024 MH Sub I, LLC dba Internet Brands