my catalytic converter is making a very loud rattling noise. Why are my check engine light not coming on? Or is this a sign that its about to fail?
catalytic converter noise on 2000 Oldsmobile Bravada
I do not work on many Oldsmobile. Does your catalytic converter have a heat shield around it ? Could it or another exhaust heat shields have stone or debris in the shields? A cat conv that fails to a point where it is rattling due to material melting and breaking up inside should set a P0420 trouble code. It may be a pending code stored in the computer.
As autotechpat said, it is probably a heat shield, but the monolithic catalytic converter may have become damaged, and is rattling inside the housing. I do not know if you can get a large stainless steel clamp and go around the body to help snug it up. If so, this will be temporary at best, and will need to be replaced eventually.