p0430
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Chevrolet · Trucks
Catalyst System Efficiency Below Threshold Bank 2
Quick Answer
Error code P0430 on your Chevrolet Trucks means: Catalyst System Efficiency Below Threshold Bank 2. This is usually fixable — see the step-by-step guide below.
Affected Models
Likely Causes
  1. Failed catalytic converter on bank 2
  2. Faulty downstream O2 sensor (bank 2 sensor 2)
  3. Persistent engine misfire damaging the catalyst
  4. Oil or coolant contamination of the catalytic converter
  5. Exhaust leak near the bank 2 catalytic converter
How to Fix It
1
Scan for related codes and review freeze frame data
2
Compare upstream and downstream O2 sensor signals on bank 2
3
Check exhaust system integrity around the bank 2 catalytic converter
4
Measure catalytic converter inlet and outlet temperature difference
5
Replace the bank 2 catalytic converter if confirmed failed
Pro Tip
This issue typically requires professional diagnosis. Attempting this fix without proper training could cause further problems.
Parts You May Need
Catalytic converter (bank 2)
Downstream O2 sensor (bank 2)
Exhaust gaskets
Exhaust hardware and clamps
Related Error Codes
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