Why Does My Car Smell Like Rotten Eggs? Causes and Repair Costs
Quick answer: A rotten egg smell from your car is hydrogen sulfide gas (H₂S). This odor is most commonly caused by a failing catalytic converter that can no longer conve…
What Causes the Rotten Egg Smell in a Car?
Gasoline contains trace amounts of sulfur compounds. During the combustion process, these compounds react to form hydrogen sulfide (H₂S), which is the chemical compound responsible for…
Failing Catalytic Converter (The Primary Culprit)
A failing catalytic converter is the most common reason for a persistent sulfur smell. When the precious metal catalysts inside the converter degrade, become clogged, or get coated wit…
Overcharged or Swelling 12V Battery
Traditional 12-volt lead-acid batteries contain sulfuric acid. If your vehicle's alternator or voltage regulator malfunctions and overcharges the battery, the liquid electrolyte will o…
Faulty Fuel System and Rich Air-Fuel Mixture
When an engine runs rich, it burns too much fuel and too little air. This is often caused by leaking fuel injectors, a clogged fuel filter, a failing fuel pressure regulator, or bad ox…
Degraded or Overheated Transmission Fluid
Modern transmission fluid contains sulfur-based extreme-pressure additives. If your transmission fluid is old, severely degraded, or leaking onto hot engine parts, it can emit a strong…
Exhaust System Leaks Venting Gases Into the Cabin
Any crack, rust hole, or loose connection in the exhaust pipes before the catalytic converter allows raw, untreated exhaust gases to escape. Instead of exiting the tailpipe, these toxi…
Read The Complete Article
Open the full Autvex article for the complete guide, details, and latest updates.
Read Full Guide