Back to all

No Yolk! Rotten Egg Smell (Sulfur Smell Causes)

March 26, 2023

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.

Tuffy Tire & Auto Service Center Waukesha
S31 W24721 Sunset Drive
Waukesha, Wisconsin 53189
262-513-9500

More articles from Tuffy Waukesha

No Fueling Around (Fuel Filter Replacement)

December 14, 2025

A driver called in to the shop the other day saying his European sports sedan had an odd problem. He was driving when his car started to slow down. Applying more throttle didn't help. He pulled over to the side of the road, shut the engine off and waited a few minutes before starting it up aga... More

No Fuel-ing! (Fuel Filter Replacement)

December 7, 2025

Your vehicle has a few filters you might be somewhat familiar with. Theres the oil filter that removes impurities from your engines oil, and a couple of different kinds of air filters that prevent contaminants from getting into the engine and the cabin. But you may not know that your vehicle als... More

No Charge (Why Won?t My Battery Hold a Charge?)

November 30, 2025

When your vehicles battery is dead, it leaves you with that horrible, helpless feeling. A dead battery means it wont hold a charge, and there are several reasons it wont. One is age. Batteries have chemical and electrical systems in them that create power, and as time goes by, they wont work we... More