hi remove the valves and sai and egr,,,now am gettng turbo chatter or flutter as they say,,av noticed my car is abit down on to en power,,,a checked all pipes,,av put my standard dv back on and yesturday i put the valves back on that are near dip stick and its still doing it...my car has stage 2 map with all the mods to suit...any help would be greatfull