Chevrolet P0420 — Meaning, Causes & Fixes
Guidance for the P0420 code on popular Chevy vehicles like the Silverado, Equinox, and Malibu.
Common Causes for a P0420 on a Chevrolet
On many Chevy models, a P0420 code is very frequently caused by a degraded catalytic converter. However, other issues are still possible.
- Failing Catalytic Converter: Especially common on V6 and V8 models after 100,000 miles.
- Exhaust Leaks: Broken exhaust manifold bolts are a known issue on many Chevy trucks and SUVs.
- Rich Fuel Condition: Leaking fuel injectors can cause a rich condition that damages the converter over time.