Common Symptoms
- Check Engine Light illuminated
- Poor fuel economy
- Reduced engine performance or hesitation
- Rotten egg smell from exhaust
- Failed emissions test
- No noticeable driveability issues in some cases
Most Likely Root Causes
- Catalytic converter degradation or internal damage
- Faulty or worn downstream oxygen sensor
- Engine oil or coolant contamination of catalyst
- Exhaust leak before or at catalytic converter
- Rich or lean fuel trim condition causing catalyst overload
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Component Location
The catalytic converter is located in the exhaust system between the exhaust manifold and muffler, typically under the vehicle chassis.
Manufacturer Notes
Some manufacturers have extended emissions warranty coverage for catalytic converters up to 8 years or 80,000 miles under federal regulations.
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