metallic rattling from exhaust

[camarocrzy]

Just recently my exhaust makes this metallic rattling noise whenever i put my foot on the gas and get going.it isnt rattling when i put it in park just when i give it some gas. i dont hear any rattles when i hit a bump like a loose clamp or something. can anyone help me out? it

[memphis_raines]

I don't know, but mine is doing the same thing. Like yours, it only rattles when the car is under load or heavy acceleration.

[camarocrzy]

Its really loud and embarrasing!Im gonna be getting a cat-back exhaust and already have the catco cat but for the time being i would like to fix it.

[majeskyb]

Ours does the same thing, but only in a certain rpm range. I know ours is a loose heat shield, but not sure which one yet. Maybe that helps?

[99v6cam]

It's either because your cat is blown or the heat shield is loose. Easy way to find out which one it is. When the car is cold and off mess with the cat to see if heat shields are loose, if not, start the car and have someone give it a little gas while you hold onto the cat (wear gloves, lol) if you feel stuff moving around inside (that's what mine does) it's blown.

[jdub4105]

Mine was doing that a while back... especially when I first gave it gas. The problem was the exhaust had come loose right behind the cat, and you could actually slide it completely off (thankfully it hadn't done that while driving). It wouldn't do it over bumps or anything, only while idling (sometimes) and when I first gave it gas it would do it for about 5 seconds or so, sometimes more. Check that out, maybe...

[Silver 99 Camaro]

Mine just started making a rattling too. But mine does it while idling in gear (not in park) and starting from a stop every time. Even if I am rolling slowly in gear it makes the noise. If anyone narrows this down please post a solution!!

[jdub4105]

I must be retarded.. I forgot to say how I fixed it. I took it to the muffler shop and the man there welded it. Ever since -- no problems. [img]smile.gif[/img]

[camarocrzy]

Ill have to check it out this weekend, but it definetly sounds like it coming from the cat just by listening from beside the car without actually getting under the car. Thanks for the input, ill let you know what i come up with. i remember i used to have a sorta buzzing noise from the exhaust while i was stopped at red lights but it would go away when i would get going but that noise is replaced by this noise.

[Silver 99 Camaro]

Same here, there was a little buzz at certain RPM's to start with and now it's become an annoying loud rattle at idle and when starting. It's 20 degrees here now so I don't know when I might be able to get underneath and check it out.

Could it be the cat? Would there be any other symptoms? Mine still accelerates fine and runs well with no codes. If it is the cat, it is under warranty on all cars for 7 years/80,000 miles by federal law.

[camarocrzy]

Mine still accelerates pretty good, ive noticed a little power loss. it was 70 degrees yesterday and now its like 32 outside. i hate working on my car outside in the cold. If it is the heat sheild does anyone know how to fix it? Isnt it crimped to the cat? Would i get a SES light if my cat went bad?

[majeskyb]

The heat shield around the cat could be loose, making the rattling noise. This doesn't effect the cat, but it's annoying. If the cat had broken up, you'd feel a large decrease in power, and from what I've heard, the exhaust would be pretty foul smelling (compared to what normal exhaust fumes smell like)

[camarocrzy]

It definetly doesnt smell unusual but i dont know what to use to keep it from rattling. I read someones post that said to use a band clamp but do they have them big enough to fit?

[memphis_raines]

Well, I found out what mine was. One of my exhaust hangers was on its way out. I was driving down the road, hit a bump, and bam! The exhaust hanger broke and my over-axle pipe was just bouncing up and down on the axle. Didn't take long to weld in a new one though. Problem solved, no more rattle.

[BLLDOGG]

just do a search. there are a million posts over rattles......