Rattling noise in the back
 

Guys
Trying to track down a rattling noise - like sheet metal tapping. Wanted to see who's encountered it or similar and had a fix for it.

So this is how I get the "noise". If I'm doing about 60kms (37mph) and in 3rd or 4th - revs are about 2500 to 3000 rpm - If i push he throttle down about 2/3rds I get the rattle noise.
Very "tinny" sound - like sheet metal rattling.
If the car is parked and I tap on the corners of the rear bumpers - around where the mufflers are located - on both sides - I get some sort of rattle.

Anyone had this and had a fix for it?

I figure I'm going to have to take the rear bumper off and drive around for a while to see if that's where the problem is coming from.

Thanks in advance.

Ken

I would check the muffler and catalytic converter heat shields as well as the rear fender braces (called "support tubes" in the parts diagrams) to see if they are loose.

+1

Also check to make sure it's not one of the little fender liner screws. Sometimes the rubber backing falls off and it pings against the inside of the fender. Noticed this in the rear in two of my 993s and was able to fix by putting a little felt adhesive thing under it.

I get this noise! Drives me nuts. I get it now over bigger bumps too.

If I hit the fender with the flat of my hand just above the rear wheel on each side I can recreate the noise but not locate it.

It is all I can hear now when I drive.

Man - it's the worst feeling.
Thanks chaps - I will get the car up on jacks on the weekend and look at those places you all mentioned.

Right - just some feedback from the last round of repairs.
I was able to eliminate most of the rattles from the back. They would appear on acceleration at low revs in 3rd or 4th.
I removed the rear bumper to inspect the sheet metal in that area.
With some adhesive backed felt I applied small portions in various areas that showed some vibration when tapping.
The task was mostly successful.
Hope this helps someone with the same issues.

https://cimg4.ibsrv.net/gimg/rennlis...31eb95a049.jpg

Have been dealing with this issue for a while but didn't take the bumper off, yet. Can you point to the areas you "taped"? Also, it sounds like you were unable to pinpoint the main culprit, did you just end up "fixing" so many contact points that you can't tell which one produced the noise?

I had similar a year or so ago. It was the rear bumper cover on the RH side, right behind the rear wheel-where it bolts to the rear fender. Removal of wheel liner allowed access to tighten the fasteners. Worth checking on yours.

I'm sure each car is going to have different places for rattles.
For me I found potential areas for rattle as follows:

Inside of the rear bumper -
Red circle - on both sides
Green circle - metal heat shield on the inside on the bumper both sides (same place that Ed describes)

Back of the car -
Blue circle - both sides - this part comes into close contact with another piece of metal.
Brown circles - both sides - main heat shield - attaches to the bottom of the rear bumper with 4 screws.

Hope this heaps - but you need to feel and tap around to see possible areas.



https://cimg2.ibsrv.net/gimg/rennlis...d6cfd8622e.jpg

Thank you so very much. Finally got around to taking the bumper cover off today and found the noise. It was indeed one of the heat shields (primarily the one just behind the right rear wheel which attaches to the car, not the bumper cover). I bent it in place and masked it with some tape.

I've found that the sunroof cables loosen up and rattle if you don't open and close it occasionally.

That is interesting as I think my sunroof or something rattles periodically. Never read this before, thanks

Mine was the heat shield. In its early years the car lived on the east coast and the attachment points had rusted. Replacement parts had to be shipped from Germany.