Any one ever dealt with recurring P0420/P0430 codes that cleared when towing? On the weekends when I tow my boat the codes will clear on their own but through the week they seem to come back. If I leave them they'll go away the following weekend assuming I get to fish but by Tuesday at the latest they'll come back. Today it got worse. I fished yesterday (codes cleared on the way to the ramp) and again this morning but went to the ramp very close to my house. This evening both codes came back. I have Torque Pro and a basic scan tool but have been unsuccessful in trying to troubleshoot mainly because I'm not sure what to look for on either to help me find my issue. Any suggestions? Really don't want to replace cats just to still have the problem. I'm not a fan of throwing parts at problems. How can I effectively troubleshoot the issue and have some level of confidence what is actually wrong?
