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Throttle Body

  1. Before installing idle air control valve, measure distance between tip of valve pintle and mounting surface. Distance should not exceed 1-1/8" (28 mm). See Fig 1.
  2. On 7.4L engine Idle Air Control (IAC) valve and IAC valves with collar on electrical connector, exert firm pressure on pintle while moving pintle from side to side until distance is correct.
  3. On idle air control valve without collar on connector, compress pintle retaining spring while turning pintle inward with a clockwise motion. Return spring to original position with straight portion of spring end aligned with flat surface of valve.
    NOTE: On 7.4L engines, the Idle Air Control (IAC) valve pintle diameter is 12 mm rather than 10 mm. Ensure replacement IAC valve pintle taper is correct.
  4. Invert throttle body assembly and place on clean, flat surface. Install IAC valve and gasket. On 7.4L engine, tighten IAC valve screws to 28 INCH lbs. (3 N.m). Tighten threaded IAC valve to 13 ft. lbs. (18 N.m).
  5. Place throttle body on holding fixture. Install throttle position sensor. Make sure throttle position sensor lever lines up with throttle actuator lever. Use Loctite on throttle position sensor attaching screws.
Fig 1: Exploded View of Throttle Body Assemblies
G12545Courtesy of GENERAL MOTORS CORP.
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