rotten egg smell
I smell Rotten Eggs: WHEN: Any time your engine is running. THE CULPRIT: Hydrogen sulfide in the exhaust, which is produced by trace amounts of sulfur in gasoline. It's supposed to be converted to sulfur dioxide in your catalytic converter. This may be indicative of a fuel-injection problem, and can be cured by a sharp mechanic. But often it means a failed catalytic converter. The bad news: A new cat is expensive. The good news is it's probably covered under warranty. Check with your dealer. Seems you fixed one already, but most often it is the cat.
Go to your local automotive store. They should probably sell a product called Cataclean. What it does is it goes in the fuel and cleans all of the possible stuff out of the cats. Even though yours are new it might still help take care of the smell. If not you might want to check the warranty on the cats.
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