My caravan with a 3.8 engine is producing code PO420, which is a catalytic converter code. I replaced both o2 sensors and code came back. Could there be anything else causing this besides the converter. I am past the 80,000 mile warrenty, so I want to try everything else before I replace the converter. Any help appreciated.

Thanks,
Wilburn Walker

 

Welcome to DF
Yes, there is. Remove the rear exhauast manifold and clean the surface. A exhaust leak will cause the same problem. If that doesn't work, then replace the converter.