P0430 Chevrolet Silverado 1500
Catalyst System Efficiency Below Threshold (Bank 2) · Powertrain Code · Medium
What is P0430?
The catalytic converter on bank 2 is not operating efficiently. Same as P0420 but for the opposite bank.
When the Chevrolet Silverado 1500 triggers code P0430 (catalyst system efficiency below threshold (bank 2)), it typically points to an issue in the powertrain system. Below you'll find the most common causes, symptoms, and repair options specific to the Chevrolet Silverado 1500.
Diagnostic data on this page is compiled from publicly available repair resources and technical service bulletins. Always have a qualified mechanic confirm the diagnosis before authorizing repairs on your Chevrolet Silverado 1500.
Common Causes on Chevrolet Silverado 1500
- Degraded catalytic converter on Bank 2 (common on high-mileage GM V8s)
- Oil consumption from AFM lifter issues contaminating the catalyst
- Failed downstream O2 sensor on Bank 2 giving false catalyst reading
- Exhaust leak before the catalytic converter
- Engine running rich on Bank 2 poisoning the catalyst
Symptoms
- Check Engine Light on
- Failed emissions inspection
- Possible sulfur (rotten egg) smell from exhaust
- Slight power loss in severe cases
- Reduced fuel economy
Notes for Chevrolet Silverado 1500
On GM 5.3L V8s with oil consumption issues, replacing the catalytic converter without fixing the oil consumption will result in premature converter failure again.