2026-06-07 · 4 min read
Bad smell in the car? 5 common causes & fixes
Musty, burning, fuel… different cabin smells can mean different problems, some safety-related.
A bad cabin smell isn't just unpleasant — sometimes it's an early sign of a fault. See which one you're smelling.
Common smells & likely causes
Musty/sour: mould in the aircond cooling coil and filter — clean the aircond and change the filter.
Burning: possibly overheating brakes, a slipping belt or overheating wiring — check soon.
Fuel: a fuel system or line leak — a safety risk, check immediately.
Sweet (syrupy): a sign of a coolant leak.
Rotten-egg: possibly a catalytic converter or fuel-system issue.
Advice
Burning and fuel smells are warnings to handle quickly. For a musty smell, do an aircond clean and change the cabin filter.