How to Diagnose Your Car Problem Using Your Nose

Drivers often catch weird smells from their vehicles when there is something wrong going on. You may think to just air it out and wait for it to go away, but often that can be a dangerous and costly mistake. Here are six vehicle smells and what kind of trouble they may be signaling:

Rotten Eggs

You probably have a bad catalytic converter if you catch a stinky smell like rotten eggs. When the cat malfunctions, it won't be able to process the hydrogen sulfide in the exhaust. You should take your vehicle to a trusted mechanic immediately.

Maple Syrup

If you catch a sweet, syrupy scent, it is most likely coolant that you're smelling. Coolant can leak out from the radiator, cylinder head, heater core, or a faulty intake manifold gasket. No matter where it originates, you should have your cooling system checked and repaired to avoid the risk of engine overheating.

Burnt Paper

A slipping clutch may emit a burning paper smell. This often occurs when a motorist repeatedly steps on the pedal, which can cause increased friction and overheat. In severe cases, your clutch could fail altogether.

Burnt Oil

The smell of warm engine oil can mean various things: low oil levels, an overheating engine, or even oil leaking onto the engine block. If you can't find an oil leak anywhere, it could also be your transmission. To be sure of where the burning odor is coming from, have a professional mechanic look at both components.


If your car A/C starts smelling like a musty basement, you could have mildew growing inside the evaporator. In some cases, you can get rid of the smell by driving with the fan on its highest setting.

Burnt Carpet

Extensive usage of your brakes can also cause a burning smell. This sign usually means that your brake pads are overheated. You should fix it by replacing your brake pads.


If you catch a whiff of any of the scents above, please take your vehicle to the experts at BG Mobile Mechanic. While some of these smells are more urgent than others, ignoring them will only worsen the problem. Our technicians can properly diagnose your vehicle at our auto repair shop and recommend suitable repairs. 

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