Upper Intake Manifold Replacement

Removal Procedure





Important: The upper intake does not have to be removed to remove the lower intake manifold.

1. Remove the air cleaner outlet duct from the throttle body. Refer to Air Cleaner Outlet Duct Replacement.
2. Disconnect the accelerator control cable from the throttle shaft and the accelerator cable bracket. Refer to Accelerator Controls Cable Replacement.
3. Disconnect the cruise control cable, if equipped from the throttle shaft and the accelerator cable bracket. Refer to Cruise Control Cable Replacement.
4. Disconnect the vacuum hose from the intake manifold for the vacuum tank.
5. Remove the power brake booster vacuum hose.





6. Disconnect the following electrical connectors:
^ The A/C compressor clutch (1)
^ The A/C compressor cutoff switch (5), if equipped
^ The Throttle Position (TP) sensor (2)
^ The Idle Air Control (IAC) motor (3)





7. Disconnect the following electrical connectors:
^ The fuel meter body assembly (1)
^ The Manifold Absolute Pressure (MAP) sensor (3)
^ The EVAP canister purge solenoid valve (2)
8. Remove the engine wire harness clip from the accelerator cable bracket.
9. Move the engine wiring harness aside.





10. Remove the accelerator cable bracket from the throttle body and the intake manifold.





11. Remove the accelerator and cruise control cable bracket from the throttle body.
Leave the accelerator and cruise control cables on the bracket.





12. Remove the PCV valve hose assembly form the intake manifold and the valve rocker arm
cover.





13. Remove the bracket for the engine wiring harness from the intake manifold stud.
14. Remove the fuel lines from the fuel meter body assembly. Refer to Fuel Hose/Pipes Replacement (Engine Compartment).
15. Remove the EVAP canister purge solenoid valve. Refer to Evaporative Emission (EVAP) Canister Purge Solenoid Valve Replacement.





16. Remove the studs for the upper intake manifold.
17. Remove the upper intake manifold.





18. Remove the upper intake manifold gasket from the groove.
19. Discard the gasket.





20. Remove the seal from the fuel meter body assembly.
21. Discard the seal.

Important: Do not immerse the assembled upper intake manifold in cleaning solvent.

22. Clean all sealing surfaces and the inside of the upper intake manifold with a shop towel and cleaning solvent.
23. Inspect the upper intake manifold for the following:
^ Cracks or other damage to the exterior
^ Cracking or damage to the gasket grooves
^ Loose or damaged bolt hole thread inserts
^ Damage to the throttle body mounting surface





24. If replacing the upper intake manifold, turn and remove the power brake booster vacuum tube fitting from the upper intake manifold.
25. Remove and discard the seal.





26. if replacing the upper intake manifold, turn and remove the PCV valve cover from the upper intake manifold.
27. Remove and discard the seal.
28. Remove the throttle body if replacing the upper intake manifold. Refer to Throttle Body Assembly Replacement.
29. Remove the MAP sensor if replacing the upper intake manifold. Refer to Manifold Absolute Pressure (MAP) Sensor Replacement.

Installation Procedure





1. Install the throttle body, if removed. Refer to Throttle Body Assembly Replacement.
2. Install the MAP sensor, if removed. Refer to Manifold Absolute Pressure (MAP) Sensor Replacement.
3. Install the PCV valve cover, if removed, using the following procedure:
3.1. Install a NEW seal (O-ring) on the PCV valve cover.
3.2. Lubricate the seal with clean engine oil.
3.3. Install the PCV valve cover in the upper intake manifold.
3.4. Turn and lock the PCV valve cover in position.





4. Install the power brake booster vacuum tube fitting, if removed, using the following procedure:
4.1. Install a NEW seal (O-ring) on the power brake booster vacuum tube fitting.
4.2. Lubricate the seal with clean engine oil.
4.3. Install the power brake booster vacuum tube fitting in the upper intake manifold.
4.4. Turn and lock the power brake booster vacuum tube fitting in position.





5. Install a NEW seal on the fuel meter body assembly.
6. Lubricate the seal with clean engine oil.





7. Install a NEW upper intake manifold to lower intake manifold gasket in the groove of the upper intake manifold.





8. Install the upper intake manifold onto the lower intake manifold.
9. If reusing the fasteners, apply threadlock GM P/N 12345382 or equivalent to the threads of the upper intake manifold attaching bolts.

Notice: Refer to Fastener Notice in Service Precautions.

10. Install the upper intake manifold attaching studs.

10.1. Tighten the upper intake manifold attaching studs on the first pass to 5 Nm (44 inch lbs.).
10.2. Tighten the upper intake manifold attaching studs on the final pass to 9 Nm (80 inch lbs.).

11. Install the fuel lines to the fuel meter body assembly. Refer to Fuel Hose/Pipes Replacement (Engine Compartment).
12. Install the EVAP canister purge solenoid valve. Refer to Evaporative Emission (EVAP) Canister Purge Solenoid Valve Replacement.





13. Install the bracket for the engine wiring harness on the lower intake manifold stud.
14. Install the engine wiring harness bracket nut.

^ Tighten the engine wiring harness bracket nut to 12 Nm (106 inch lbs.).





15. Install the accelerator and cruise control cable bracket to the throttle body.
16. Install the accelerator and cruise control cable bracket nuts.

^ Tighten the accelerator and cruise control cable bracket nuts to 9 Nm (80 inch lbs.).





17. Install the accelerator control cable bracket to the throttle body and the intake manifold.

^ Tighten the accelerator control cable bracket studs and nuts to 12 Nm (106 inch lbs.).





18. Connect the PCV valve hose assembly to the intake manifold and the valve rocker arm cover.





19. Position the engine wiring harness.
20. Install the wire harness clip to the accelerator cable bracket.
21. Connect the following electrical connectors:
^ The fuel meter body assembly (1)
^ The manifold absolute pressure (MAP) sensor (3)
^ The EVAP canister purge solenoid valve (2)





22. Connect the following electrical connectors:
^ The A/C compressor clutch (1)
^ The A/C compressor cutoff switch (5), if equipped
^ The throttle position (TP) sensor (2)
^ The idle air control (IAC) motor (3)





23. Connect the vacuum hose from the vacuum tank to the intake manifold.
24. Install the power brake booster vacuum hose to the intake manifold.
25. Install the cruise control cable, if equipped to the throttle shaft and the bracket. Refer to Cruise Control Cable Replacement.
26. install the accelerator control cable to the throttle shaft and the bracket. Refer to Accelerator Controls Cable Replacement.
27. Install the air cleaner outlet duct to the throttle body assembly. Refer to Air Cleaner Outlet Duct Replacement.