Scott,

I too have a sort of dull thudding noise from the nearside rear of the car. This happens while at low speeds and doesn't matter if you are on or off the throttle. There is a reported problem with the bushes on the anti-roll bar drop links on the WRX (i'm gonna'have them replaced soon). Because yours happens only when you come off the throttle it can't really be due to this, sorry.

I do however get a noise when coming of the throttle now and again, but this is more of a high pitched sound. It seems that a common problem is for the heatshield to crack and vibrate. (btw which heatshield anyone, the turbo one isn't currently on my car so it can't be this!).

Hope you get it sorted soon, and i wounldn't worry about it,

Tone.

You may of seen me post this problem before, but please bear with me as I have yet to solve it and it's starting to drive me mad.

I have a 93 WRX. The problem is that on over-run (i.e when lifting off the loud pedal) at anything above 2,500rpm. I get a faint 'DONK...DONK...DONK...DONK' or even a 'DONG...DONG...DONG...DONG' noise from the rear of the car, possibley even the rear nearside.
This is occasionally replaced by a 'BBBRRRRRRR' louder noise as if something is hitting the underside.

Neither noise is particularly loud, but it is noticeable.

I origionally thought it may be the diff, and after taking it to a local mechanic/Subaru Rally driver, they thought it may just be the exhaust.
Thinking it may be the baffles in the standard rear silencer, I replaced it with a Magnex SS rear section (SHAME). However, the noise persists. But the car in general know sounds pretty groovy.

I have been under the car on countless occasions to try and find the cause, looking for metal to metal contact and wedging bits of rubber in here and there to stop movement of mounting bushes etc...I've even shone a light upto the neather regions surrounding the DIFF assy but have yet to find a solution or any signs of contact.

SUMMARY...

Am I trying to find a problem that doesn't actually exsist i.e do all early WRX do it due to low sound proofing.

If it is a genuine problem even with the diff, I don't mind, I just want an answer or solution.
I just don't want to pay a garage huge sums of Labour Money whilst they try and find the cause.

Thanks to all who try to help.....

I have got a 93 WRX.
Is the noise more like a zzzzzzzzz when you let off the pedal which only lasts for a second or two, or is it an intermittent does it when it feels like it type noise ?
I wouldn't worry.
Jim.

Does it only make this noise whilst moving ???

If not get it up on a ramp and get someone to rev and lift off to recreate the noise whilst you are under the car listening for the noise.

If its only when moving it will be very dificult, perhaps a session on a rolling road to try and find it.

I think it's something shifting and knocking under reverse load i.e when lifting off.

You can bang it down through the gears at whatever revs you like and the noise doesn't change, which must rule out a Diff problem.

In fact at times I think the noise has gone, then just to P*** you off, DONG....DONG...DONG, there it goes again.

It's a similar sound to what I used to get on the front of my old RS1600i which was the Suspension Bushes in the track control arms.

As I said before, I may just be paranoid and it's perfectly normal ????