Hi all I have a 2000 Camry XLE V6 and the check engine light is on, getting code PO420? I was told I need to replace the cat converter. My question is how do I tell which one I have to replace? I have one coming off the front exhaust manifold and two are on the longer pipe that connects to the intermediate pipe. The car is running great and having no issues at all. I was also told to try a additive which can clear the code and help me pass emission inspection. Any one use that or have any success with it. I really don't drive this car that much but it has to be legal so I'm trying to fix it correctly but trying not to spend a lot of money on a car worth maybe $1000. Thanks for the help guys

 

Did you read the code? Any other information with this code or any additional codes?