Well, I'm finally going to the garage tomorrow morning to change the cats. I'm getting installed 2 Magnaflow cats part# 94106 and we'll see what happens there. If my misfires stop, then great news, if not, I'm going after the coil packs and spark plugs. But then again, I don;t want to go that far. Although one night, I jacked up the front end of my car and rattled both cats too see if both were rattling and you can hear both were finished. When leaving that night, I didn;t have any misfires for at least two days. So I honestly think, it's the cats that are clogged. But we'll see tomorrow. I'll keep you up to date tomorrow.