i have a 2000 camaro 3.8 liter V6 . i keep hearing this rattling noise coming from my exhaust. I checked and nothin seems to be loose. I have flowmaster cat backs. I thought it was my catalytic converter but got a new one and the noise continues. Any info please. I would greatly apprieciate it .

 

Have you checked ou the heat shields on the exhaust system? They tend to rust out and then rattle about.

 

no, how do i check the heat shields ? Where do i look?

 

Go under the car and follow the exhaust plumbing, you will find sheet metal shields around the exhaust system whenever it gets too close to the bodywork, over the cat and mufflers, etc.. Also check all bolts and hangers, and shake the pipes while you are under there.

Also, keep in mind that the V6 exhaust makes a pretty rattly sound when you don't use stock mufflers.

 

alright thanx for the info

 

I have this same problem. I had this before I added the exhaust system. ITs a rattle that comes up when the car is under load. I also thought the baffles in the cat were bad, so I replaced. This didnt help. I took it to the shop, and they placed the blame on a sheild on the O2 sensor right after the cat. Boy were they wrong. I have rattled everything I can under that car, and can still not find it. I even put it up on ramps. Put it in drive, and revved it with my brothers crawling under it trying to find the sound.. No luck. Any more ideas?

 

I get this sound of what I think is small rust particles being thrown about inside my exhaust somewhere. The sound only occurs on startup and the colder the car is the longer it takes to go away. (generally 3-6 sec)

Is it the same thing these guys are having or is it something I can get check out or would replacing my exhaust system with flowmasters from the cat and back help?

 

Could be the insides of your cat or your muffler rusted or fell apart and are getting blown out the tailpipe.