Posts Tagged: check engine light flashing

Code P0420: What it means and what to do about it

Learn what code P0420 means and how to fix it A P0420 code means your catalytic converter has failed an efficiency test. In other words, it’s not removing harmful combustion byproducts from the exhaust. Many people think that the way to fix code P0420 is to replace the oxygen sensors. That’s wrong. In fact, the vehicle computer can’t even come to the conclusion that your catalytic converter has failed the efficiency test if your oxygen sensors are bad. So, don’t waste your time and money on oxygen sensors. What to … Read More