What is making the rattling noise in my catalytic converter and how do I fix it? And how serious is it?? It is on a 1995 Saturn SC-2 with 138,000 miles. Anyone can help me??

David Johnson90, March 2009

the rattling noise is the honeycomb element inside of it and you need to replace the whole converter otherwise it will fail MOT, for a temp fix you could take the cat off and smash the honeycomb out but will fail mot its better to replace.

hope this helps

funkbuddy, May 2009