Smell Rotten Eggs? Check Your Car's Catalytic Converter — And Your Paint
That unmistakable smell of rotten eggs is the tell-tale sign that you will likely need to replace your car's catalytic converter. Catalytic converters change the hydrogen sulfide (from gasoline) to sulfur dioxide as it runs through the car's exhaust system. That rotten egg smell means that the sulfur dioxide isn't efficiently getting past the catalytic converter, which means it cannot efficiently be released through your exhaust. The sulfur dioxide can also damage the paint around your car's exhaust pipe.
Bad Smell? Bad Trouble?
Sulfur dioxide is a federally permissible emission from your car's exhaust into the air. Although it is a permissible emission, it doesn't mean that sulfur dioxide is good for the environment. Sulfur dioxide is also a component of acid rain. Acid rain, over time, can damage your car's paint job.
If your catalytic converter gets clogged over time, or if it malfunctions for any reason, then it cannot process the hydrogen sulfide from your gas engine. The more the converter malfunctions, the worse the smell of rotten eggs. That rotten egg smell is the signal to get your car's catalytic converter checked by your mechanic as soon as possible. If you wait, you may get yourself in trouble when your car fails to run.
Rotten Egg? Immediate Repair?
As a rule, if the odor of rotten egg worsens, see your mechanic as soon as possible. If the smell comes and goes, you may have a bit of time before you have to take your car to the car repair shop. If you wait too long, however, your car will cease to run. One sign of imminent converter failure is a decided lack of acceleration. Pressing on the accelerator will not increase the speed of your car. This is a mechanical emergency.
Repairing the catalytic converter, and perhaps the entire exhaust system, can be very expensive as some newer cars have two catalytic converters. You also may have to deal with some minor body work and a minor paint job depending on the amount of wear and tear on your vehicle due to sulfur dioxide.
The good news is that with better exhaust systems, sulfur dioxide emissions are less than they were in the past, partly due to the science of catalytic converters and better emission standards. But for now, fuel combustion still makes up most sulfur dioxide emissions. Perhaps with more non-combustion, electric vehicles hitting U.S. roads, rotten eggs and acid rain will eventually become nothing but a memory.
Contact an auto repair shop for more information.
