untraceable noise.
 

hey guys I seem to have an odd problem with my 83' 928s. When i start the car i hear a noise that can only be described as a rattleing loose heat sheild. almost like if you were to take a shovel and scrape it along a driveway but it increases and decreases in intensity. It persists if the car is at idle however if you select drive or reverse it dissapears. Also while driving its not there. When the car is turned off the noise kind of farts real quick. Its very hard to describe, if i knew how to post a video i would.

Now I have checked underneeth the car while it is runing and I cannot for the life of me find out where its scource is. There are no lose heat sheilds from the front of the car, nothing on the exhaust that i can see. it almost sounds like it is coming from the oil pan.

Does anyone have any information that can be of help. i know its very vague but its all io really have to go on for now. Anything at all would be greatly appreaciated.

Sounds like a bad torque tube and/or torque converter bearing

5sp or auto ?

If auto = poss flex plate rivets

If 5sp = poss missing nylon bush on the ball at the top of the clutch release arm or loose guide tube in the clutch.

Could be loose exaust joint somewhere that gets loaded up when the motor is loaded while driving stopping it rattling.

is there any way to check the torque converter? any specific test?

Intermiitent loose components in cat(s)?

Not untraceable, merely untraced.

With the car on a lift and a sharp ear or a stethoscope it would be the work of a moment to trace the source of the noise.

It does sound like drivetrain noise though.

I narrowed a similar noise to loose cat internals. It goes away when driving because the exhaust pressure holds the loose pieces in place. Get one of those mechanic stethescopes with a long metal probe and hold it against the cat, etc. You can also use a long screwdriver held to your ear or a length of vac hose but those approaches are generally less effective.

thanks guys i will try all of these approachs as soon as my audi is out of the garage. i need to start paying somone ls to do this **** lol. I nvr get a break.

and to answer earlier questions it is an automatic.

Is it louder under the car or under the hood.
near the rear or near the front

It sounds about where the cat is, its louder from under the car

Hi Bobby. I bumped Troy928's thread about broken flex plates for you. I suspect you are having the same problem--broken flex plate. If so it is likely related to previous damage to the car that resulted in a slight bend in the juncture between the engine and torque tube, if the break is the front flex plate, or between the torque tube and the transmission if the break is the rear flex plate. In either case i think you are going to need a new torque tube.

Jerry Feather

I believe I have the same thing. I posted it in a video on this site today. Go here-->>

https://rennlist.com/forums/928-foru...er-here-2.html