964 T - knock coming from passenger side rear

[turbo ride]

Guys-
Over the last week or so a sound has gotten a little worse - I know diagnosing a sound over the interzwebz is nigh on impossible but I'm hoping there is common culprit back there.

Car is a '91 Turbo and has H&R height adjustable coilovers, FWIW.

It's an inconsistent knock that seems to be coming from the passenger side rear - comes and goes, sometimes happens going over a big expansion crack in the pavement, but often doesn't. Sometimes it seems to happen if I let off the throttle quickly. I jacked up the rear of the car and could not feel any play/movement in the suspension. But I did not check tightness on any bolts, I admit. Another thought was maybe a motor mount or tranny mount?

I have a TON to learn about this car - thanks in advance. P.S. if this would be bettter suited for the 964 forum not Turbo forum - let me know - thanks.

Thoughts?

Brandon
'91 911 Turbo
'01 Audi S4

[full quack]

My first thought would be the rear sway bar bushings / drop links, but admittedly, I do not know what style is on a 964T.

The stock rear sway bar body mounts on a 930 are very weak, and tend to crack-n-break off easily. So your noise may be from there as well.

Worth a little look-see at least.

Mark

[turbo ride]

Seems like a good thought - will certainly look for that - thanks.

Any other thoughts please chime in - thanks guys.

Brandon
'91 911 Turbo
'01 Audi S4

[Miguel Antonett]

+1 on the bushings.

What about some pictures of the car??? Might get more interest...

[JFairman]

Sounds like somethings loose back there when the rear suspension is worked up and down.
Along with checking every motor mount and rear suspension nut and bolt under the car look in the motor compartment in back on each side of the arched cross member.
It could be a loose nut on the top of a rear shock absorber.

I doubt the oil tank would come loose but 3 nuts on studs hold it on from inside the motor compartment too.

[turbo ride]

JFairman - yeah I was thinking the same thing - so was "disappointed" when I felt no play when the back wheel was dangling off the ground. Will get under there tonight with tools and check everything.

Miguel- shall I take it that I should always post a pic in the first post? :-)

Here's a pic because you asked :-)

Brandon
'91 911 Turbo
'01 Audi S4

[turbo ride]

Ok fellas had a chance to crawl under there and found the passenger side drop link bolt (that connects through the sway bar) a little loose - got it good n tight, aka PFT. Same side as where I heard the noise coming from so my hopes are high. As much as I want to, prolly not going to drive the car tomorrow so I may not know until Thursday if this was the solution. Then again - I'm thinking maybe I'll go get some gas tonight...I know a great station about 25 miles away :-)

Thanks for the pointer guys!

Brandon
'91 911 Turbo
'01 Audi S4

[Miguel Antonett]

You're right about the picture rule... Good looking car!

What other mods, I can see the wheels, heights, and exhaust... what else?

What about a picture of the engine bay?

If that bolt was loose, that's probably the end of it. Be sure the bolt is not worn out (i.e. reduced diameter by friction/knocking/rubbing)

Enjoy it!

[turbo ride]

So that was the issue - went for a drive last night - noise was totally gone. So then a headlight bulb went out LOL. Going to replace both and keep the good one as a spare. Also taking the opportunity to replace the currently old/deformed headlight bucket seals. One side done, one to do tonight.

Miguel- the car is mostly stock. It has the "3.6 S" (I think thats the model) splitters up front (in carbon), Euro/clear front corner markers and blinkers, H&R adjustable ride height coilovers, Genuine Speedline for Porsche wheels, and Fabspeed tips (with gutted wastegate cat/muffler). Fabspeed cat bypass should arrive tomorrow and I will add a little boost over the winter and do the WUR. Then I'm calling it good.

Again - thanks for the pointer to the sway bar and link, guys - the car is now completely squeak and rattle free.

Brandon
'91 911 Turbo
'01 Audi S4