Common Symptoms
- Check Engine Light illuminated
- Slight decrease in fuel economy
- Possible sulfur or rotten egg smell from exhaust
- Vehicle may fail emissions testing
- No significant drivability issues in most cases
Most Likely Root Causes
- Catalytic converter degradation or internal substrate damage
- Exhaust leaks upstream of catalytic converter
- Faulty or contaminated downstream oxygen sensor
- Engine running rich causing catalyst contamination
- Use of low-quality fuel or fuel additives
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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 floor.
Manufacturer Notes
Many manufacturers require verification that upstream oxygen sensors and fuel delivery are functioning correctly before catalytic converter replacement.
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