I recently got a terrible metallic rattle noise that goes away at higher rpm, and declines with rising engine temp. I went through the exhaust with a rubber mallet and everything seemed tight. The sound seems to be from the passenger side cat. I'm surprised how loud it is.
Is there a way to test for a bad cat? I haven't gotten any computer warnings.
Is there a way to test for a bad cat? I haven't gotten any computer warnings.