6 Car Smells And Odors You Shouldn’t Ignore

Did you know that you can tell a great deal by how your car smells? In fact, your sense of smell can alert you to a variety of mechanical issues with your car and help you to identify issues before they become worse. Learn how to identify and troubleshoot six of the most common smells in your car below.

1. Rotten Eggs

If there is a smell of rotten eggs in your car, chances are that the smell is from hydrogen sulfide, a chemical found in your car’s fuel that is described as smelling like rotten eggs.

This may indicate the mechanical issue is with your catalytic converter. Hydrogen sulfide, found in the exhaust, is produced by sulfur in the fuel. Once it enters the catalytic converter, it should convert to sulfur dioxide. If you smell rotten eggs, the catalytic converter is not doing its job and calls for an inspection by a professional.

It may also be a mechanical issue with the battery. If a battery is frozen, overcharged, or has otherwise shorted out, it may vent gas. It is essential to have the vehicle inspected immediately as the sulfuric acid in batteries can corrode away at other vital engine parts.

Read more: Why Does My Car Smell Like Rotten Eggs?

2. Gas

Gasoline has a pungent and undeniable odor. The key to diagnosing a gas smell depends on timing. If you just recently topped off your tank, it may be nothing more than a sloppy gas fill up, and the smell will quickly dissipate as you drive.

However, if the smell persists, it may be attributable to a fuel tank leak, cracks in the fuel lines, leaking fuel injectors, spark plug issues, problems with the fuel pressure regulator, evaporative emission control system failures, concerns with exhaust fumes, or trouble with the gas cap.

Any smell of fuel coming from your car could result in a fire hazard. With most of these issues, it is important that you bring your vehicle into a repair shop right away as these types of leaks are a potentially dangerous problem that need to be addressed immediately.

Read more: Why Does My Car Smell Like Gas?

3. Vinegar

There could be a variety of reasons as to why your car smells like vinegar. It could just be a bag of leftovers forgotten in the back seat.

But a more common cause of the smell is mold produced from condensation in your car. When running, air conditioners produce a great deal of condensation. When condensation accumulates inside the dashboard and fails to dry completely, the damp and humid environment becomes the perfect space for bacterial growth and mold in the air conditioner (AC) unit.

And when unmaintained, what you are inhaling every time you turn on your AC is mold.

You can solve this by airing out your air conditioner unit. If the smell persists, you may need to deep clean your AC system or replace the air filters.

Read more: Why Does My Car Smell Like Vinegar?

4. Burning rubber

One of the smells you should be most concerned about is the smell of burning rubber. The smell of burning rubber can indicate a variety of concerns, such as a loose hose, an oil leak, a clutch issue, a coolant leak, a damaged belt, brakes that are too hot, an electrical shortage, or that a foreign object is stuck to the car.

Among the most common causes of a burning rubber smell is friction. Friction can occur when a loose rubber hose becomes pressed against a hot part of the engine, a drive belt freezes and spins against the pulley, or when brakes do not have sufficient cooling time and begin rubbing up on each other.

Read more: Why Does My Car Smell Like Burnt Rubber?

Furthermore, other burning smells, such as the smell of burnt toast, can indicate a short with the electrical system or an issue with burning insulation. The smell of burning carpet can also indicate that your brake pads are overheating.

The smell of burning anything is a sign that there could be a potential fire hazard lurking beneath the hood of your car. Address this immediately before the issue gets worse.

5. A sweet or sugary smell

If you are smelling something sweet or sugary, you may be smelling an engine coolant leak. This could signal that there are performance issues and an overheating engine. Check the underside of your car for fluids, and search for puddles underneath your engine compartment. You may also be able to spot a leak near the passenger footwell in the front seat.

6. Hot Oil

If you smell hot or burning oil, the first thing you should do is check the oil dipstick in your car. If you are low on oil, it could mean that you don’t change the oil in your car often enough or that there is a leak.

Smelling hot oil when there is nothing on the ground may indicate a small leak, possibly a valve cover gasket. If smoke is escaping from the exhaust, your car is leaking oil internally, burning it and sending it out the tailpipe. To diagnose it properly, bring your car to the mechanic.


Your sense of smell is an important one. In the context of car ownership, it is an important sense that can alert you to many dangerous malfunctions in your car that you should not ignore.

The smell of rotten eggs, gas, vinegar, burning rubber, something sweet, or hot oil can indicate a variety of issues with your car. Take your car to a professional expert to inspect and solve the underlying issues of the strange smells in your car.