Rattling & no one knows where its coming from

[Voodoo410]

I have a 1994 Camaro (V6). There is a very loud rattling coming from underneath the car (I think the exhaust...), I've taken it to the Chevy dealer to see if they could find out what was wrong. The Chevy dealer tightened the bolts and clamps for the exhaust and everything under the car. That didn't stop the rattling. Then they said it was the Catalytic Converter was bad & was causing the rattling. They replaced the Cat; but the rattling continued and I found out that there was nothing wrong with the Cat in the first place. The Chevy dealer has no idea what is causing the rattling noise and neither do other mechanics. When standing outside the car, it sounds like the noise is coming from about the middle of the car. WHen inside the car, the noise sounds like it's coming from the engine compartment on the passenger's side. It doesn't start to rattle until the car has been warmed up. The muffler & cat are brand-new. Car has had all servicings done and runs strong, but the rattling has gotten so loud that even if I turn the stereo all the way up, I can still hear it.

Does ANYONE have ANY clue as to what could be causing it and how to fix it?

[96 T-Top Bird]

I will put $20 that its ur Y-Pipe.

I had the same problem, thought it was the cat, so replaced it, nothing.

Thought it was the heat shield over the cat, took it off, nothing.

Thought it was the exhaust, had it all tightened, nothing.

Thought it was heat shields over manifold, nothing.

Took it to a new place told me it was the y-pipe

The y-pipe is a 2 piece pipe. There is this small pipe w/ a larger pipe covering the outside, so its like 2 pipes in one.

The smaller pipe thats inside rusted out and started to form a rattle.

Ur best bet is taking it to a place and have them bang on the y-pipe a little and they'll realize thats the problem.

A new pipe is around $575 cause it comes w/ the converter in one piece. I said screw that!

Bought a used y-pipe off someone on this board who had headers installed and WHA-LA, no more rattle!

I can almost guarentee thats the problem, wont know for sure unless i heard it..but stop by a shop and point that out to them and see what they have to say.

Muffler shop i went to said it was a common problem w/ Firebird/camaro's cause of the sh*tty design of the pipe.

Hope this helps...any questions, email me :D

[Sunset2002]

I had a rattle around the same area on my 02. At first the dealer thought it was in the dash. Then they looked at the exhaust and said that it was shifted. They realigned the exhaust and now the rattle is gone.

[stagen]

Is it the stock exhaust or do you have an after market exhaust on there? If after market check and see if the pipe going over the axle is resting or hitting your panhard bar. My Borla does that and I have to adjust it every few months.

[bluecmaro96]

holy crap 575.00 for cat and y pipe? he** my headers were only 450.00 and an extra y pipe is 150.00 you all know the cat is warrantied for 8 years 80000 miles right?

[stagen]

LOL - no kidding, I got my Borla, basically brand new for $300, Hi-Flo CAT for $100, and the headers I just ordered were $197.00 shipped.

[zlightning]

Ok if it is your y-pipe I would just goto an exhaust shop with a good rep and have them cut your existing on off and weld on a custom made one. IT should cost you more then 150. I forget the cost of mine I will check latter for you.