I know this has been talked about on other forums but nobody is really detailed on where the smell is coming from and when.

I have a 95 mystique GS Zetec and every time I drive around for a while and the car gets to running temp I smell a really nasty(I think it's a sulfer smell) coming from the engine compartment. I have no CEL light on and I have more than enough performance, no problems with the car yet at 111,000 miles.I dont think it would be the o2 sensor because I have plenty of power and not haveing a CEL light on doesnt indicate a problem.

Just wondering if anybody has had this specific smell/problem. If so please reply with advice/fixes for this problem.