2000 Pontiac Firebird Exhaust Rattle

DMORROW7

MEMBER
2000 PONTIAC FIREBIRD
6 CYL
2WD
AUTOMATIC
123,000 MILES

Ok. I believe this may be a very hard thing to describe but here goes nothing.
I have a rattle in exhaust, have gone to three exhaust shops and no one can figure it out. Shaking exhaust does nothing.
I do not hear any rattle noises while idling, park, etc. Until I start driving BUT again I do not hear the noises until I let off the gas pedal and coast or start to press the brake then I hear the noise. It sounds like metal to metal contact. Again I only hear it rattle when I let off the gas, usually have to press the brake but I do hear it just coasting as well.

1 Reply

ERNEST CLARK

MECHANIC
1,730 POSTS

Shaking the exhaust may not always duplicate a sound, even if there is a loose exhaust or object inside of the exhaust.

Has anyone suspected your converter. A lot of times, a part of the (Comb) inside the converter will break off and rattle as you drive.

Also, if you have a rusted/loose manifold flange, you can experience a rattle as the engine torques side to side. But if you shake the exhaust pipes, it may not be enough to make the rattle.

You can also have a loose baffle inside of the muffler. You can bang on the converter and muffler with a rubber mallet and try to find out if there's something floating around in there.