...THEN its sits about 8-900rpm. If I turn the AC off it goes up to 1000-1100 rpm then does that bounce thingy. The engine sounds like I'm casually tapping the gas when it does that. It threw 3 codes, 0171, 0174 and 0402... Any clue? I've read IAC, EGR, PCV elbow, tensioner, etc.... Like could...