Could a bad motor mount cause a rattle in my exhaust? I've been tring too track down a rattle, And i put new exhaust on front to back! And i have the same rattle that i started with? Nothing is touchin anywhere's under the car. It seams to be right between the header and cat. Could a motor mount make it rattle?

 

I'm betting its the heat shield somewhere.

 

every heat shield is gone!

 

the heat shields would have been my first guess, but you you don';t have any??

does it only rattle at certain rpm's?? only when your sitting still??

cause i had a bad motor mount about 6 mounths ago, it did make my exhaust rattle but only when i was sitting still, plus it vibrated the hell out of my steering wheel

 

does the exhaust have equal space on either side the WHOLE way back...

Usually where it bends in front of the gas tank it can rattle or knock there if it's not PERFECTLY centered in the exhaust channel.

Check to see the clearances are the same all the way back... if they are then it's prob. not that unless one of the exhuast hangers is shot...

Make sure everything is tight first then try jiggling the exhaust from side to side where the cat is... also try jiggling it from the exhaust tip...

If that still doesn't do it it may be some pieces of the cat rattling but that's less likely.

You can also tap it with a hammer to find a rattle... you give it a light whack and it should rattle where ever it is when it's running... then it's just a matter of tracing where the sound is coming from and what's causing it...

obviously this is easiest under a lift... but it's doable on the ground... just harder to get an exact idea of where the sound is coming from.

 

I had a rattle in my exhaust. I had a JR high flow cat. I took the cat off and the middle honeycomb section was loose and rattling around..So i had to bust out back section and break it up with a big screw driver and the same with the middle section..So now theres only one honeycomb section in there but it still works