What causes a exhaust system to smell like rotten eggs?.?

Question

After driving my S320 car for 70 plus miles and park it. It's exhaust smells like rotten eggs. What causes this?.

Answer 1

That rotten egg smell can mean a bad catalytic convertor.

Answer 2

Almost all the above answers are almost correct. By design, the catalytic converter converts the exhaust byproducts into hydrogen sulfide and water. Sometimes this mixture is a little off balance and creates sulfuric acid which is only one molecule away but that doesn't happen all that often. Sulpher is the chief byproduct of rotten eggs which is why the smell. Under ideal conditions the converter would not produce enough sulpher to cause the strong smell but it almost always produces a mild smell and you just don't notice it. Have you ever been driving and smell the sulpher when cars pass you? Don't be concerned about the smell unless it's just so strong you can't stand it. As you put some more miles on your car, the smell will lessen as the catalytic converter "wears out" some.

Answer 3

It can mean several things. The two people that posted above are correct. Also, it could be the type of gas you are using with that specific car. My mom used to have a car, that whenever she put in the cheapest gas, it would smell like rotten eggs. As soon as she switched to a higher grade gasoline (specified by the car's manufacturer) it was fine.

Answer 4

Running too rich of a fuel mixture--could be bad O2 sensor(s) or other fuel related problem with computer, sensors or engine fuel control components. Don't wait too long to fix as it could plug up the catalytic converter eventually if it becomes constant.

Answer 5

Could be bad O2 sensor, but the check engine light should be coming on for this. May be bad gas, or a stopped up converter. I've had stopped up converters before, they usually smell like sulphur, "burnt matches" when they stop up. But who knows, that could be it. But if your check engine light is on, I would go with th o2 sensor, if not, try buying the good gas, then move on to the converter.

Answer 6

usually a bad cat but it could be other things like bad oil or problems with your engine. my advise is to take it in and get it checked out

Answer 7

Its a by product of your catalyst is called hydrogen sulphide

Answer 8

that wonderful aroma is caused by your catalytic converter

Answer 9

bad catalytic convertor.

Answer 10

its a bad o2 sensor more then likley