Anyone have experience or seen this online? To clean the carbon buildup out of the cat. I saw someone do this on youtube and the comments were flooded with people saying it worked and cleared their p0420 code and that they had a noticeable improvement in performance without replacing their cat. I plan on replacing my cat, but I still would like to know about this as a temporary improvement until I do! My main concern is, could seafoam destroy the metals or anything structural inside the cat? Or would it only eat the carbon buildup? TIA!