GM Service Manual Online
For 1990-2009 cars only

Removal Procedure

Important: The intake manifold, throttle body, fuel rail, and injectors may be removed as an assembly. If not servicing the individual components, remove the manifold as a complete assembly.

  1. Remove the air cleaner outlet duct. Refer to Air Cleaner Resonator Outlet Duct Replacement in Engine Controls.
  2. Relieve the fuel system pressure. Refer to Fuel Pressure Relief in Engine Controls.

  3. Object Number: 898468  Size: SH
  4. Disconnect the air conditioning (A/C) compressor pressure switch electrical connector (2).
  5. Remove the harness clip from the cylinder head.

  6. Object Number: 1204792  Size: SH
  7. Disconnect the mass air flow (MAF)/intake air temperature (IAT) sensor electrical connector (1).
  8. Remove the harness clips from the fuel rail.

  9. Object Number: 898331  Size: SH
  10. Disconnect the following electrical connectors:
  11. • Main coil (1)
    • Electronic throttle control (ETC) (2)
    • Fuel injectors (3)

    Object Number: 1209783  Size: SH
  12. Perform the following steps in order to disconnect the fuel injector electrical connector.
  13. 8.1. Mark the connectors to their corresponding injectors to ensure correct reassembly.
    8.2. Pull the connector position assurance (CPA) retainer (2) on the connector up 1 click.
    8.3. Push the tab (1) on the connector in.
    8.4. Disconnect the fuel injector electrical connector.
    8.5. Repeat the steps for each injector electrical connector.

    Object Number: 898329  Size: SH
  14. Disconnect the generator electrical connector.

  15. Object Number: 898326  Size: SH
  16. Disconnect the following electrical connectors:
  17. • Evaporative emission (EVAP) purge solenoid (1)
    • Knock sensor (2)
    • Manifold absolute pressure (MAP) sensor (3)
    • Main coil (5)
    • Fuel injectors (4)
  18. Remove the electrical harness clips from the fuel rail.
  19. Remove the knock sensor harness electrical connector from the intake manifold.

  20. Object Number: 1386395  Size: SH
  21. Remove the positive crankcase ventilation (PCV) hose.

  22. Object Number: 898349  Size: SH
  23. Remove the heater water shutoff valve actuator inlet hose from the intake manifold.

  24. Object Number: 898353  Size: SH
  25. Remove the evaporative emission (EVAP) purge solenoid vent tube by performing the following:
  26. 15.1. Remove the EVAP tube end from the solenoid.
    15.2. Squeeze the EVAP pipe quick connect fitting retainer together.
    15.3. Remove the EVAP tube end from the vapor pipe.

    Object Number: 898352  Size: SH
  27. Remove the vacuum brake booster hose from the rear of the intake manifold.

  28. Object Number: 899740  Size: SH
  29. Remove the upper engine wire harness retainer nut (1).
  30. Reposition the upper engine wire harness aside.

  31. Object Number: 825839  Size: SH
  32. Remove the intake manifold bolts.
  33. Remove the intake manifold.

  34. Object Number: 492770  Size: SH
  35. Remove the intake manifold gaskets (1) from the intake manifold.
  36. Discard the old intake manifold gaskets.
  37. If necessary, clean and inspect the intake manifold. Refer to Intake Manifold Cleaning and Inspection .

Installation Procedure


    Object Number: 492770  Size: SH
  1. Install NEW intake manifold gaskets (1) to the intake manifold.

  2. Object Number: 825839  Size: SH
  3. Install the intake manifold.
  4. Apply a 5 mm (0.20 in) bead of threadlock GM P/N 12345382, (Canadian P/N 10953489) or equivalent to the threads of the intake manifold bolts.
  5. Notice: Refer to Fastener Notice in the Preface section.


    Object Number: 63222  Size: SH
  6. Install the intake manifold bolts.
  7. Tighten

    1. Tighten the bolts a first pass in sequence to 5 N·m (44 lb in).
    2. Tighten the bolts a final pass in sequence to 10 N·m (89 lb in).

    Object Number: 899740  Size: SH
  8. Route the electrical harness into position over the engine.
  9. Install the engine harness bracket nut (1).
  10. Tighten
    Tighten the nut to 10 N·m (89 lb in).


    Object Number: 898352  Size: SH
  11. Install the vacuum brake booster hose to the rear of the intake manifold.

  12. Object Number: 898353  Size: SH
  13. Install the EVAP purge solenoid vent tube.

  14. Object Number: 898349  Size: SH
  15. Install the heater water shutoff valve actuator inlet hose to the intake manifold.

  16. Object Number: 1386395  Size: SH
  17. Install the PCV hose.
  18. Install the knock sensor harness electrical connector to the intake manifold.

  19. Object Number: 898326  Size: SH
  20. Connect the following electrical connectors:
  21. • EVAP purge solenoid (1)
    • Knock sensor (2)
    • MAP sensor (3)
    • Main coil (5)
    • Fuel injectors (4)

    Object Number: 1209783  Size: SH
  22. Perform the following steps in order to connect the fuel injector electrical connectors.
  23. 13.1. Install the connectors to their corresponding injectors to ensure correct reassembly.
    13.2. Connect the fuel injector electrical connector.
    13.3. Push the CPA retainer (2) on the connector in one click.
    13.4. Repeat the steps for each injector electrical connector.
  24. Install the harness clips to the fuel rail.

  25. Object Number: 898329  Size: SH
  26. Connect the generator electrical connector.

  27. Object Number: 898331  Size: SH
  28. Connect the following electrical connectors:
  29. • Main coil (1)
    • ETC (2)
    • Fuel injectors (3)
  30. Install the electrical harness clips to the fuel rail.

  31. Object Number: 898468  Size: SH
  32. Connect the A/C compressor pressure switch electrical connector (2).
  33. Install the harness clip to the cylinder head.

  34. Object Number: 1204792  Size: SH
  35. Connect the MAF/IAT sensor electrical connector (1).
  36. Install the air cleaner outlet duct. Refer to Air Cleaner Resonator Outlet Duct Replacement in Engine Controls.
  37. Install the fuel fill cap.
  38. Connect the negative battery cable. Refer to Battery Negative Cable Disconnection and Connection in Engine Electrical.
  39. Use the following procedure in order to inspect for leaks:
  40. 24.1. Turn the ignition ON, with the engine OFF, for 2 seconds.
    24.2. Turn the ignition OFF for 10 seconds.
    24.3. Turn the ignition ON, with the engine OFF.
    24.4. Inspect for fuel leaks.