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No Yolk! Rotten Egg Smell (Sulfur Smell Causes)

February 28, 2021

The pungent smell of rotten eggs can send people running for the hills.  So when that odor is inside your vehicle, yikes!  Yolks!  The good news is that a trained service technician can search the source of that smell and stanch the stench… that comes from another words that begins with S.  Sulfur.

Fuel contains small amounts of hydrogen sulfide, but they're enough to stink up a vehicle when it's not properly burned.  You may know that the smell of rotten eggs can often be a sign of a catalytic converter that isn't working the way it should.  That could be due to age, damage or an abundance of oil that's clogging it up. 

If a sensor in charge of managing the fuel has failed, the engine can run with too rich of a fuel mixture.  That can overload the catalytic converter and allow some of the byproducts to escape without interruption from the chemical reaction that is supposed to prevent them from going out the tailpipe.

There's another possibility, but it's usually only in stick shift vehicles.  That's leaking, old transmission fluid.

Catalytic converter repairs are best left to a professional. Technicians at your vehicle service facility have equipment and training that can help them pinpoint the cause of this funky fragrance.  Once the cause is found, repairs made and/or parts replaced, the smell should go away fairly rapidly.

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Troy, Michigan 48083
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