Why Does My Car Smell Like Rotten Eggs?


No one wants a lingering odor in their vehicle, especially if it is as potent as the foul smells of rotten eggs. Unless you forgot about your groceries in the car, the issue isn’t rotten eggs themselves. The smell is most likely sulfur coming from the fuel or exhaust system. When your vehicle cannot “digest” its fuel, it can leave a lingering odor from unburned gas. 

If this foul smell persists, it should be thoroughly investigated and diagnosed by a professional mechanic. Here are the top 3 common explanations for why your vehicle smells like sulfur:

  • Broken Catalytic Converter - The most common culprit for this smell is a bad catalytic converter, a component that makes up a chunk of your exhaust or emissions system. The “cat” is supposed to transform the hydrogen sulfide in your gas into odorless sulfur dioxide. If certain gasses aren’t being properly handled, you should always turn to the catalytic converter for clues.
  • Failing Fuel Regulator - Sometimes, the problem extends farther than the catalytic converter to include a fuel component. A fuel pressure sensor or regulator is in charge of the use of fuel in your car. When this failure occurs, it can lead to a clogged catalytic converter.
  • Bad Transmission Fluid - Last but not least, the rotten egg smell can also be caused by too many missed transmission fluid services. This fluid can leak into other areas of your car and emit this unpleasant smell.

Diagnosing Vehicle Smells with Quality Auto Repairs in Arlington, TX

The best way to get down to the bottom of the problem and get rid of the lingering smell is by bringing it to a trusted auto repair shop like Euro Car Tech. At our Arlington auto service shop, we have solutions that you can trust. From emissions system repairs to transmission fluid exchanges, we do it all. 

We welcome you to bring your car to the expert team at Euro Car Tech today!