GM Service Manual Online
For 1990-2009 cars only
Makes 🢒 Buick 🢒 2009 🢒 Lucerne 🢒 Engine 🢒 Engine Mechanical - 3.9L 🢒 Upper Intake Manifold Cleaning and Inspection

    Object Number: 1866469 Size: SH
  1. Remove the throttle body bolts and nuts.
  2. Remove the throttle body.
  3. Remove the throttle body studs, if required.
  4. Remove the manifold absolute pressure (MAP) sensor (1).
  5. Remove the evaporative emission (EVAP) purge valve bolt (2).
  6. Remove the EVAP purge valve (3).

    7. Object Number: 1665698 Size: SH
  7. Remove the EVAP purge valve isolator, if equipped.

    8. Warning: Refer to Cleaning Solvent Warning in the Preface section.

    Warning: Bodily injury may occur if the cleaning solvent is inhaled or exposed to the skin.

  8. Clean the intake manifold with solvent.
  9. Dry the intake manifold with compressed air.
  10. Inspect all gasket mating surfaces for nicks or cracks and replace if necessary.

    11. Object Number: 1665698 Size: SH
  11. Install the EVAP purge valve isolator, if equipped.

    12. Object Number: 1866469 Size: SH
  12. Inspect the EVAP purge valve seal for damage and replace if necessary.
  13. Install the EVAP purge valve (3).

    14. Caution: Refer to Fastener Caution in the Preface section.

  14. Install the EVAP purge valve bolt (2) and tighten to 16 N·m (12 lb ft).

    15. Object Number: 1665700 Size: SH

    Note: Ensure that the EVAP purge valve isolator is installed properly as shown, with the isolator covering the top and bottom of the purge valve bolt hole flange. Failure to do so may cause improper EVAP purge valve operation.

  15. Inspect the MAP sensor seal for damage and replace if necessary.
  16. Install the MAP sensor.
  17. Install the throttle body studs, if required. Tighten the throttle body studs to 6 N·m (53 lb in).
  18. Inspect the throttle body seal for damage and replace if necessary.
  19. Install the throttle body.
  20. Apply threadlock GM P/N 12345382 (Canadian P/N 10953489) to the throttle body bolt and nut threads.
  21. Install the throttle body bolts and nuts and tighten to 10 N·m (89 lb in).