allroadDC

On a drive back from New Hampshire last weekend. I developed a strange issue with the suspension.

On normal relatively high-speed highway driving (say, 80mph) the allroad has always been pretty rock-solid -- with the H-sports anti-roll bars added it has been even better. But it now has developed a strange feel. It is almost like it floats, or is jittery at speed -- almost like it will get away from you. Very disconcerting. Keeping the car at level one (402 mod has been done) minimizes this feeling, but is still there.
When you manually select the car's level, the light above "man" on the suspension control no longer lights up.

I hooked up the laptop and VAG to see if the car might tell me what is going on and I don't get much. The only fault is an intermittent one -- "1399 Relay for Level Control Compressor (J403) 28-10 Short to B+". The car's suspension goes up and down on slectiopn without issue ir incitent -- like normal. Except, I don't think that automatic ride height is working, where the car will lower if you go above a certain speed. With the VAG software (Ross-tech) I did an "output tes" on the suspension -- which will test "level up" at each corner, as a whole, and test the LED display. The car passed all the output tests (including the LED above "man", mentioned above). I am also getting a speed-sensitive noise that seems to be coming from the front wheels (sort-of, a wap-wap-wap, that starts out low and rises in frequency with increasing speed). At least visually with the wheels on, I don't see anything wrong (I broke my hand, so I am not going any further than that).

Does anyone have any idea what is going on? I'll probably change the relay with the intermittent fault on the off chance that is the problem. I'd like avoid taking it to a dealer, as I have learned not to trust them (they'll tell me to replace the entire suspension). ;-( Has anyone experienced anything like this? Any suggestions or insights into this problem? Thanks.

audiallroadin'

apparently they can loosen over time.

allroadDC

I thought of that, too as it might explain some of the loose feeling. They look alright, but will need to get the car up to have a better look. Still, it wouldn't seem to be the cause of some of
the suspension control issues (no auto level, no "man" LED).

paulroad

the rear bar's bolts have pulled through the end link. Perhaps installed inside out, which is a common intstall mistake or without the washers.

allroadDC

The rear bar and the end links all look fine. The H-sport installation was done with washers and the right way around.

Nappy

My wifes old car had tire defects. The tread was delaminating from the carcus and the car really felt squirelly (sp??).

allroadDC

the tires are fine

BSteely

An airspring is, in the end, a pretty dumb thing. By that I mean it can't really screw up and cause a problem like you describe. At least not any way that I can think of. Could it be damping failure? That sounds more like a thing that could make the car squirrely. If I were in your shoes, I'd try rocking the car on its suspension to see if one of the corners seems to lack damping.

allroadDC

That is my view -- that there is a problem with damping control. I tried rocking the corners but didn't notice anything abnormal. Is the damping controlled electronically, and therefore might there be a potential problem with the module? Unfortunately, I don't get a fault code for it, or any of the dampers.