An effective catalytic converter converts harmful gases to less-harmful water vapor
and oxygen, but a defective one will emit unpleasant-smelling chemicals into your
car’s exhaust system.
If you detect the smell of rotten eggs in your car, this could be an indicator that your
catalytic converter has failed. At Auto Fix in Franklin, they offer testing services to
check your catalytic converter and help ensure its effectiveness.
Sulfur Smells
If your car smells of rotten eggs it could be due to issues with its catalytic converter.
This honeycomb-shaped piece of equipment functions as a filter by processing
harmful chemicals produced during fuel combustion into water vapor and carbon
dioxide; when these are left unprocessed they exit through your exhaust system
emitting an offensive aroma that gives off bad fumes.
An efficient catalytic converter should convert hydrogen sulfide present in gasoline
to innocuous sulfur dioxide gas. A fleeting whiff of sulfur may be noticeable when
revving up your engine; however, any persistent smell that reminds you of rotten
eggs could indicate something is amiss.
Problems associated with fuel filters can range from being simple, such as being
clogged up with debris, to more serious ones such as having an oxygen sensor or
mass airflow sensor that malfunction. Such issues send an overly rich mixture or raw
gas directly into the converter causing overheating resulting in that characteristic
“rotten egg” smell that most commonly comes with these vehicles.
Rotten Egg Smells
If your car emits the scent of sulfur or rotten eggs, this could be a telltale sign of its
catalytic converter‘s malfunction. This exhaust system component is responsible for
transforming harmful toxins like hydrogen sulfide (which smells of rotten eggs) into
safer gases before exiting through its tailpipe; when broken, however, it won’t be
able to convert these harmful gases to non-odourous sulfur dioxide gas and will
instead leak out with harmful emissions through the tailpipe.
Your catalytic converter’s catalyst is composed of platinum. As gasoline burns inside
your vehicle, it produces hydrogen sulfide and other sulfur compounds which should
normally be converted to odorless sulfur dioxide by your converter’s platinum
catalyst. However, when its performance breaks down or otherwise malfunctions it
may fail to do this job and hydrogen sulfide may enter the exhaust system instead. A
rotten egg smell could indicate failing fuel pressure sensors, clogged filters or aged
transmission fluid preventing its proper function and rendering your catalytic
converter incapable of carrying out its duties properly.
Burning Smells
If you detect a burning smell while driving your car, it could indicate that its catalytic
converter has failed. This could happen if its fuel injectors or ignition coils start
misfiring, sending spark plugs dumping fuel into the exhaust system and
overheating its converter. Fuel may also leak in through leaky mufflers or exhaust
pipes or it may reach it directly through rich fuel mixtures (or physical damage such
as hitting rocks which causes denting in its shell) damaging its internal honeycomb
structure resulting in its collapsed honeycomb breaking apart leaving unburned fuel
behind and emitting an unpleasant rotten egg smell while driving.
A rotten egg smell may also be caused by engine issues like a damaged head
gasket, piston rings or valve seals that allow too much rich running that
contaminate the catalytic converter with oil. Any mechanical issues which lead to
such smell should be evaluated by an experienced mechanic immediately.
Sewer Smells
Detecting sewer odors could be a sure sign that the gases released by an
underperforming catalytic converter have entered your home and are entering
through any cracks in its walls or otherwise entering through doorways or openings
in walls, compromising health by emitting hydrogen sulfide and other dangerous
gases which contain hydrogen sulfide, making your health at risk. Therefore, it’s
crucial that if any such smells appear within your residence it be addressed as soon
as possible by calling in professional plumbers immediately.
Your vehicle’s catalytic converter works to reduce emissions from its engine while
increasing fuel efficiency by changing hydrogen sulfide into sulfur dioxide – and
when this fails, odorous sulfur or rotten egg smell may come wafting from your
exhaust pipe and its smoke darker than usual.
Follow your vehicle’s recommended maintenance schedule to prevent clogging of its
catalytic converters. A blocked converter can negatively impact fuel economy,
engine power, and even other parts of your car.