Recently i have been having rattling noises coming from under my car usually when i first put my car in drive3, reverse or cruising in low gear. So i went to my mechanic and had him check under my car to see if anything was lose with the cat, pipe, or muffler from me scraping/ hitting from having lowered car. He cam to the conclusion that i might have busted the muffler from it being scraped/hit and that nothing seemed wrong w/ the pipping or cat. Should i go to a muffler shot or something to have it checked out also? I really don't want to buy a new muffler and have the sound still there.

thanks for the help

 

Check the heat shields on your cat, also have your muffler checked by an exhaust shop. Could also be one of your motor mounts going bad

 

I would also go with heat shield some how i had some rocks in mine and it would rattle at certain rpms/speed/etc....kind of sounded like a rock in a soda can....

 

does sumone have a diagram or can point out where the shield is ? thanks

 

It's around the cat, you can't miss it

 

I had a similar issue with a rattling at certain rpms at idle. I thought it was the heat shield and all of that, but mine was a busted cat. Mine started as a little rattle every now and then, and as the weeks went by it got louder and happened more often.