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augidog · Joined: 03 Mar 2003 Posts: 1360 Location: New Jersey

I have a rattle that seems to be behind the front seat center area. I've had increasing vibrations that I thought was a failed motor mount. Shifting is fine, maybe a little harder to slip in occasionally. Today when the car was off -shifting was rough to engage.I had a new clutch put in over the winter,they dropped the trans to do it(they were not Porsche mecs

).I feels and sound like a universal giving out. It rattled louder on turns. Its louder now and I thought something would fall off on the way home.
My thoughts are:
1st shift coupling
2nd bearing(though I don't think it would rattle as loud as it is)
3rd Connecting sleeve.
Help- its my daily drive.
I have a donor trans
_________________
1978 924 95 mile daily driver.
Audi TB/POR174M/High Flow Cat/2.25" exhaust
I knew that positive thinking thing wouldn't work.

augidog · Joined: 03 Mar 2003 Posts: 1360 Location: New Jersey

now its huming in the rear diff -out of gear.
_________________
1978 924 95 mile daily driver.
Audi TB/POR174M/High Flow Cat/2.25" exhaust
I knew that positive thinking thing wouldn't work.

Smoothie · Posted: Wed Nov 08, 2006 2:21 pm Post subject:

If it's still there with clutch pedal out, in neutral, with engine shut off and car rolling, then you can rule out the coupling.

You're sure it's not a CV joint? -Though their dying sound is usually described more specifically as a rhythmic clunking rather than a vibration, rattle or humming..
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"..it's made in Germany. You know the Germans always make good stuff."

'82 924T, US version, dark green metallic, 5 speed Audi 016G gearbox

Llamaguy · Joined: 02 Jul 2003 Posts: 711 Location: Indiana

possibly the heat shield.
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1987 924S Guards Red
1997 Suzuki Tl1000 Supersport

augidog · Joined: 03 Mar 2003 Posts: 1360 Location: New Jersey

Not heat shield issue- a drive train issue for sure.
I first thought it was a loose exhaust part.
On turning out of gear to the left I would hear the rattle.
I did not think I would make it home .it got louder but I could still shift and go. It would disapear at high speeds. If i decelerated than it would rattle. Only in gear.
Would a bad bearing cause such a rattle.
I would love it to be the cv's
It is not safe to drive it now.
_________________
1978 924 95 mile daily driver.
Audi TB/POR174M/High Flow Cat/2.25" exhaust
I knew that positive thinking thing wouldn't work.

924RACR · Posted: Thu Nov 09, 2006 1:29 am Post subject:

All I can say is you're gonna need to get under there and start looking for loose stuff. Your list is a good place to start...
_________________
Vaughan Scott
Webmeister
'79 924 #77 SCCA H Prod racecar
'82 931 Plat. Silver
#25 Hidari Firefly P2 sports prototype

Smoothie · Posted: Thu Nov 09, 2006 3:07 am Post subject:

I'd start with a check of the lug nuts, cv bolts and the stub axle nuts.
_________________
"..it's made in Germany. You know the Germans always make good stuff."

'82 924T, US version, dark green metallic, 5 speed Audi 016G gearbox

D Hook · Joined: 02 Nov 2002 Posts: 3158 Location: Omaha, NE

I found a few of my CV bolts loose and backed out when we were doing a brake job on my car awhile back.
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'80 924 n/a SOLD

augidog · Joined: 03 Mar 2003 Posts: 1360 Location: New Jersey

What might have been damaged/bent when the "less than qualified "mechanics dropped the trans to do the clutch?
I felt the vibration start in a much smaller degree back then.
They said it was because of a unbalanced flywheel or misfire.
I new it was not and thought I just may not have noticed the vibration with a failing clutch.
Is the trans and possible torque tube a difficult swap? I may have a chance to pick up another running 924.
_________________
1978 924 95 mile daily driver.
Audi TB/POR174M/High Flow Cat/2.25" exhaust
I knew that positive thinking thing wouldn't work.

924RACR · Posted: Fri Nov 10, 2006 2:01 am Post subject:

Possible bent torque tube shaft, or trans input shaft?
_________________
Vaughan Scott
Webmeister
'79 924 #77 SCCA H Prod racecar
'82 931 Plat. Silver
#25 Hidari Firefly P2 sports prototype

Viking · Joined: 30 Jan 2003 Posts: 107 Location: Oslo, Norway

Jack up the car, and check if your rear drums are properly on. Me and my mechanic forgot to put in a lockingpin once, and the castellated nut came loose, and with it - the whole drum. I heard sounds that seemed to come from somewhere in the back of the car, couldn't find anything loose, went for a MOT test, and the mechanic asked me if I had any plans to drive far ... he though a wheelbearing was totally shot, but "luckily" it was "only" a loose drum. It wasn't hard to feel at all, the wheel was loose when you put your hands on the side of, and tried to twist in the direction it should not move. (While jacked up of course) The sound it made when turning made it clear to me that it was a vibrating noise, and I lose count how many times I want over the wheelbolts to make sure they were tight.

The sound was very audible turning in one way, totally gone while turning the other way, and sometimes present when driving straight ahead.

About CV joints:
When I had three very damaged CV joints the first time, it gave a loud clunck whenever I let go of the clutch after changing gears. The second time when I had one go even worse made horrible noises while turning at slow speed in a parkinghouse - clunk, clunk, clunk.

I hope you can find the source of the noise.

isuras2 · Joined: 17 Jun 2005 Posts: 458 Location: Phoenix, AZ

augidog: Did you ever find the cause of the vibrations?
_________________
Rob
'80 931 (sold)
'80 924 NA (sold)
Former Omaha Crew

augidog · Joined: 03 Mar 2003 Posts: 1360 Location: New Jersey

Rasta Monsta · Joined: 12 Jul 2006 Posts: 11733 Location: PacNW

More likely the spring was already dead and the sudden decel caused the rubber portion to finally let go.
_________________
Toofah King Bad

WeiBe (1987 924S 2.5t) - 931 S3