Posts Tagged: P0420 trouble code

What causes catalytic converter failure and P0420

Causes of catalytic converter failure and P0420 A P0420 trouble code Catalyst System Efficiency Below Threshold (Bank 1), and P0430 Catalyst System Efficiency Below Threshold (Bank ) usually mean you’ll be in the market for a new catalytic converter. A P042o or P0430 is almost never a bad oxygen sensor Yes, I know that many online sites tell you to fix a P0420 with a new oxygen sensor. In rare cases, that might fix the problem. But for the vast majority, replacing the oxygen sensor is really wishful thinking and … Read More