Posts Tagged: P0420
Catalytic Converter Cleaner: Miracle Fix or Temporary Band-Aid?
Why Catalytic Converter Cleaner Rarely Works Long-Term Quick Summary A catalytic converter cleaner may, in certain cases listed below, temporarily eliminate a P0420 or P0430 trouble code. 1) Your cat is borderline failing and has carbon buildup or deposits that are reducing the converter’s efficiency 2) The underlying problem is due to excessive oil consumption, coolant leaks, or running rich, which has fouled but not damaged the catalyst 3) You catch it early, before the substrate is physically degraded Catalytic Converter Cleaners Don’t Work When: 1) The catalyst substrate is … Read More
Toyota Scion P0420
Fix code P0420 Toyota Scion If you own a 4-cylinder Toyota or Scion vehicle and get a check engine light with trouble code P0420, welcome to the club. This has been a persistent problem with these vehicles. To get right to the point, the problem is bad software. Toyota has updated it. But that’s not all. If you don’t maintain this vehicle EXACTLY as Toyota says, you can accelerate this problem. It all starts with misfires and not changing your oil. Misfires send unburned fuel down into the catalytic converter where it’s … Read More
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