It's hard to explain the sound/vibration that I'm experiencing but it's at lower RPM's and only after the cars been driven quite a bit. It almost sounds like grinding but not as harsh, or bogging. It doesn't sound like it's coming from my engine compartment but I can recreate it when I'm in park and lightly rev the engine. Although it doesn't happen very often? I know this is an odd request/noise but maybe someone can point me in the right direction. I've gone through and ensured my entire exhaust is torqued so it's not a loose bolt.

 

I had a similar issue. The rattle ended up being my cat was loose. The dealership found the problem and fixed it during my oil change. I didn't think much of it because it hardly ever made the sound and the car drove fine.

 

Yeah same it's running fine. I didn't run up to the cats but ill jack up my car tonight and look into it! Thanks duke

 

Well today on the freeway my car started making a knocking metal sound from the undercarriage, this is getting to be an issue and I'm not sure it's the cats because it sounds like it's coming further back than that. Maybe the diff or mufflers? Could that be the case?

 

had similar issue. turned out to be the u- shaped bracket that bolts to the bottom of the bell housing and bolts to the down pipes. mine rusted right off so they were vibrating against each other. vibrations resonate through the exhaust system pretty easily so its hard to pinpoint sometimes.



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