I have a 97' grand am, lately when i park the car and get out to go in a store or whatever and then go right back to the car. I get in and it smells like crap in there. I mean literally it smells like rotten egss or something. I have heard that when the catalytic converter is going bad it will sometimes smell bad. Is this true. Or do you have any other ideas as to what could be causing the smell?

Nate