Unnerving Noise at low idle
Thread Starter
Racer
Joined: May 2003
Posts: 294
Likes: 0
From: Albany OR
Unnerving Noise at low idle
Every once in a while I get a vibration/noise while I'm in drive (A4) and at a total stop. The idle will dip down a little lower than normal, right around 500rpm. I then get a vibration and associated noise with it throughout the whole car. It is a low tone like a mount is loose or the bushings in the torque tube are going bad or something is vibrating against the body. Any ideas? I know this is pretty vague its going to be pretty hard to diagnose. What happens when the torque tube bushing start to go? Is it a constant noise? Thanks for any help.
Le Mans Master
Joined: Oct 1999
Posts: 8,205
Likes: 40
From: Tucson AZ
Re: Unnerving Noise at low idle (vettatude)
It could be any of those things, but is probably the exhaust system. If you can put it on a lift or jack stands, check out the system for an obvious "rub" area, and/or figure out how you can limit the movement of the pipes. :yesnod: :)
Burning Brakes
Joined: Dec 2000
Posts: 993
Likes: 5
From: Cincinnati Ohio
Re: Unnerving Noise at low idle (vettatude)
vettatude,
See this TSB link: http://corvetteactioncenter.com/kb/q....php?qstId=260
The "fix" eliminated the rumble in my 1999 C5 coupe (A4). Good luck.
See this TSB link: http://corvetteactioncenter.com/kb/q....php?qstId=260
The "fix" eliminated the rumble in my 1999 C5 coupe (A4). Good luck.
Le Mans Master
Joined: Apr 2001
Posts: 5,331
Likes: 39
Re: Unnerving Noise at low idle (carpe dm)
It could be any of those things, but is probably the exhaust system. If you can put it on a lift or jack stands, check out the system for an obvious "rub" area, and/or figure out how you can limit the movement of the pipes. :yesnod: :)
When I've got mine in the air the catback touches to swaybar but not when on the ground.
BTW: when my torque tube went south I heard a sound like a screw driver being put on a metal lathe. This was the sound of the bolts shearing off. Your issue is probably not the torque tube.
Racer
Joined: Apr 2001
Posts: 287
Likes: 0
From: Plano, Texas, USA TX
Re: Unnerving Noise at low idle (vettatude)
vettatude, I'm afraid I can't offer any possible solutions for you but I will be monitoring this thread. As I believe I have the same symptoms on my A4 as you describe. I hear and feel a low growling rumble maybe once per week, only when stopped and in gear. When this occurs and I shift to Neutral, the sound and vibration stop completely. In my case, it sure sounds like it is coming from the tran/torque converter area and not up front related to any belt or pulley. Hope both you and I detect what's going on soon so we can resolve the problem. btw, I just ordered a Corsa Daytona exhaust so I'll be able to verify whether this noise is related after I swap out the exhaust in a couple of weeks.
Thread Starter
Racer
Joined: May 2003
Posts: 294
Likes: 0
From: Albany OR
Re: Unnerving Noise at low idle (DC5)
Well guys, I think its the belt rumble problem. I don't want to shell out the $350 for the new style alternator though. I might just try a new 2001+ tensioner and a new belt. I am faily convinced this is the problem. I have been paying closer attention to when it happens, and it basically fits the TSB descriptions to a tee. If that tensioner doesn't work, there are aftermarket units that are adjustable with a threaded bolt and nut, so you could crank down just a bit more.... I know I know, not too hard, don't want to pull too much on the crank......
