Have you ever thought maybe the rotten egg smell is coming from rotten eggs?

 

Lol no.. I will just wait to see if a dash light comes on.. I'm not to worried about it now..

 

Did you, per chance, just come from a few high revs or hard accelerations?

Cat's make this smell when they're driven hard, sometimes when everything else is up to temp, but they're not, and other times just because they will.

 

He lives on a uphill slope so I was on the accelerator going up to his house..

 

There's a great big uphill slog to get out of town here, it stinks, badly, all normal cars just trying to do 50 on the highway.

Engines under load make hotter gasses, this heats up cats big time, it's just what they do. The chemical reaction is just hydrogen sulphide, basically the same gas given off by rotten eggs.

 

I noticed tonight when I give the car a little gas I notice a fluttering noise from the exhaust.. I'm wondering if its a leak and that's why my miles per tank seems to be not as good..

 

Your in cabin air filter sits right behind your battery, you probably need a new battery or to change the filter out. Bad batteries will smell like rotten eggs.

 

I have a newish optima yellow top.. I haven't smelled it since I made this post so who knows.. I did notice some holes in the shield that goes over the cat so I've been scraping them from being low..

 

Do you live in an area where they put salt on the roads in winter? Causes a definite smell on our cars.

 

Yeah i do..

 

Bad gas can also cause that smell. If you have purchased fuel somewhere you haven't bought gas from in the past, try on your next fill-up to go to one you usually use.

You can also go to places like Midas for a free exhaust inspection. They can use an infra-red thermometer to determine if the catalytic converters are doing their job properly. That's how I found my clogged cats on my Lincoln Mark VIII.

 

Nice i will have to get them to check it out.. thanks!!

 

That's likely it, then, mine smells like that after driving on salted roads; some kinda reaction with the hot exhaust parts.

 

It's quite possible that the damage to the cats combined with salted roads is contributing, but the hard driving warming the cat up harshly is just a normal reaction to the process. A sulphurous smell is common.