My 2000 pathfinder vg33e has a miss when holding speeds and using light throttle and a rough idle when the ac is off. have tried seafoam and countless others. have replaced plugs, fuel filter, bpt valve. when egr was disonected after my bpt valve blew up it didnt miss when holding speed but still had the rough idle what could be causing this. i also have a knock sensor code that hides in the background.