1. desertdriver

    Help - how to diagnose a bad catalytic converter?

    Ok, need some help with this please: 05 KJ, 280k miles. Brand-new spark plugs (the correct copper type) and refurbished all 6 coils at the same time. Had a P0172 code pop up. Cleared code and ran some injector cleaner through with a full tank of gas. Code returned along with p0456. Bought new...