I had an old OEM exht. sys. on my 91'Integ. I notice everytime my car warms up about 30 minutes. I had this ugly smell under my car (smells like burnt rubber) I took it to the shop to replace new piping, resinator and muffler. After 2 weeks.. I still have the smell under the car. I know I didn't change the Catylic-Conv., still have the old Cat on. You think the smell is coming from their?.

 

I've heard the cat smells like rotten eggs.