Posts Tagged: OBD2 codes

P0420 or P0430 No Other Codes? Here’s What I Check First

P0420 or P0430 With No Other Codes: How I Diagnose It Without Wasting Money Quick Summary If you have a P0420 or P0430 with no other codes, don’t automatically assume the catalytic converter is bad without additional testing. In my experience, the converter is often the culprit, but it’s not the only possibility. I always begin by confirming there are truly no additional engine, fuel trim, misfire, or oxygen sensor codes, then inspect for exhaust leaks and analyze live scan data before recommending an expensive converter replacement. Following a logical … Read More