Slight rattle while accellerating + P0420

[Need4Camaro]

My car has a rattle under acceleration, a very disturbing vibration which seems to be coming from the rear of the car but I cant be sure, but I did start noticing it after my new fuel pump was installed, but before it - I cant remember because my car really wasnt really all that drivable... I also have a P0420 code... would a cat cause a vibration under accelleration if its bad?

[ssms5411]

Re: Slight rattle while accellerating + P0420

I would check your heat sheilds, esp. the one on the CAT.

[Need4Camaro]

Re: Slight rattle while accellerating + P0420

I would check your heat sheilds, esp. the one on the CAT.

If one so happened to fall on the cat, would that cause the cat to become inefficient? just wondering, I wasnt sure if they needed to breathe or not.

[pace2006]

Re: Slight rattle while accellerating + P0420

When I had a new differential installed the exhaust got tucked up a bit too high and caused the car to feel a bit off, along with causing a cat code to pop up. After readjusting it (ie. giving one of the exhaust hangers a good shove), the exhaust went back to its normal spot and no more codes or rough rattling feeling. Might check it out.