[Chiefpontiac]

Your symptom could also indicate a faulty choke pulloff. The choke pulloff on a Q-Jet is responsible for more than one function. One of them is sensing the load on the engine. When vacuum is high, as at idle, the pulloff holds the secondary air valves (flaps) closed until the engine revs up and vacuum drops. When you floor it from a stop, vacuum drops and the pulloff holds the secondaries closed momentary until the rpms come up to match the load. If the pulloff is faulty, the spring Dan discussed is the only thing holding the secondary air flaps closed and you will get a bog or flutter upon acceleration.