Alpine Ski Racer

Hi,

I am new to this site, so indulge me if I ask stupid questions...

I have a 2002 allroad, stock w/most of the options, with about 57K miles. About 1 year ago (maybe a little more), the suspension compressor failed. The dealer eventually replaced the compressor, but ever since then it has been sporadically making a bizarre noise. The noise is very similar to what it sounds like when you drift over the rumble strips at the side of the highway, a loud kind of low frequency rumbling, and lasts for only a second or two at most. I have not been able to perceive any sort of pattern to the occurences, however I can regulate the suspension height without hearing the noise, so I am not certain that it is caused by a permanent compressor issue. It always comes from the rear left quarter, and rear seat passengers can feel the vibration. I have not noticed any negative effect on the ability of the suspension to be adjusted, but my wife freaks out about it all the time, and I would prefer to track this gremlin down before something does go bad. It *seems* to happen more frequently in hot weather.

Two dealers have looked for a problem but found nothing, and despite the fact that i reported this a long time ago, of course it is not covered anymore as i am above the mileage limit.

Any suggestions greatly appreciated!

happy allroader

I don't know how it is mounted, but maybe a loose bolt, missing rubber washer, or such is causing this. If you can put it on a lift and have someone run it up and down through levels 1-4 maybe you can track it down by looking from underneath.

glidar

<ul><li><a href="https://forums.audiworld.com/allroad/msgs/124025.phtml">https://forums.audiworld.com/allroad/msgs/124025.phtml</a</li></ul>

Alpine Ski Racer

I see you got a lot of constructive feedback, too...

Just got a call from the dealer; third attempt, they hear nothing. Is it me, or are half these guys incompetent?

Synmag

Unless it's one of those ramps you drive on that lifts up the car by the wheels. If you look at the archives people have had expensive damage to their car from not putting it in jack mode before going on a hoist. My mechanic told me it should be ok on a hoist without jack mode as long as you don't adjust the ride height!

Sorry, I can't help with your current problem, just trying to help you avoid further problems.

Dr.quattro

The compressor turning on and off to fill the reservoir with pressurized air. Mine does it, although it is not as loud as you describe, nor can any passengers feel it.

It sounds like the current compressor may not have been installed properly?

want

2nd that, and do it on an alignment platform.

Ollie

My compressor makes a similar noise after it has been running to fill the reservoir and turns off. While it runs, it is relatively quiet but just before shutting off it vibrates a bit more and probably touches the sway bar (i have h-sports which make the tight fit there even smaller), especially if suspension height is at lowest level. This has not caused any reliability problems, just the occasional noise.

By the way, you can adjust the height without the noise when the reservoir is full enough to provide the necessary air and not running the compressor. As suggested in other posts, you could observe from underneath while running the compressor. Also, see if having the suspension at highest settings makes a difference - if yes, this would indicate that it is touching a body part. You could then install a piece of foam to reduce the vibration, or try to alter the installation angle of the compressor. A couple years ago (before h-sports) many of us experimented with fixes after using the A6 sports sway bar and discovering that the compressor hits it and makes serious noise; you could search for older posts on the forum. Good luck!