Hello I had to get my Prius's catalytic converter replaced after thieves sawed off the original and also ripped out the lambda sensor. After replacement, the engine light comes on, and the mechanic with his diagnostic tool showed me a p0420 coff with some message about oxygen level bank 1. I have been back to the mechanic and he has tried to check all the parts he's replaced but he can't get to the bottom of why this error is showing. Anyone know what the real issue might be? Thanks
I don't have any experience with this one but if you do a google search for "P0420 priuschat" you'll find lots of links to read... The more of it you read the the easier it will be to solve. Make sure to read enough so a random wrong commenter that never got corrected doesn't throw you off.
Did your mechanic erased the stored DTCs after the installation? He's supposed to do that before handing over the car to you. Sometimes, if it's an aftermarket one, you need some drive cycles completed, before the ECU would realised what's being done.
