Common Symptoms
- Check Engine Light illuminated
- No noticeable drivability issues in most cases
- Slightly reduced fuel economy
- Failed emissions test
- Possible slight sulfur smell from exhaust
Most Likely Root Causes
- Degraded or failing catalytic converter
- Exhaust leak before or at catalytic converter
- Faulty downstream oxygen sensor
- Engine oil or coolant contamination of catalyst
- Rich or lean fuel mixture damaging catalyst over time
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Component Location
The catalytic converter is located in the exhaust system between the exhaust manifold and muffler, typically underneath the vehicle.
Manufacturer Notes
Some manufacturers require drive cycle completion after catalyst replacement to allow the PCM to relearn catalyst efficiency characteristics.
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