Strange Exhaust Smell
Urgency: ModerateDifferent exhaust smells indicate different problems. A rotten egg smell typically indicates a failing catalytic converter or rich fuel mixture. A sweet smell suggests a coolant leak into the combustion chamber. A burning oil smell could mean oil is leaking onto hot engine components or being burned in the cylinders.
Need to read your codes?
An OBD-II scanner lets you read and clear diagnostic trouble codes from your vehicle's computer. Most scanners work with any car made after 1996.
Browse OBD-II Scanners on AmazonPossible Causes
- Failing catalytic converter
- Rich fuel mixture
- Coolant leak (head gasket)
- Oil leak onto exhaust
- Worn piston rings
Related OBD-II Codes
When to See a Mechanic
A rotten egg smell should be checked within a week. A sweet smell (coolant) should be checked immediately as it could indicate a head gasket issue.
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