Upper Intake Manifold Replacement

Removal Procedure

Important: You do not have to remove the upper intake manifold in order to remove the lower intake manifold.





1. Remove the engine cover. Refer to Engine Cover Replacement.
2. Remove the air cleaner assembly. Refer to Air Cleaner Assembly Replacement.
3. Disconnect the PCV tube from the air cleaner outlet duct.
4. Remove the air cleaner outlet duct from the throttle body. Refer to Air Cleaner Outlet Duct Replacement.
5. Disconnect the accelerator control cable from the throttle shaft and the accelerator control cable bracket. Refer to Accelerator Controls Cable Replacement.
6. Disconnect the cruise control cable, if equipped from the throttle shaft and the accelerator control cable bracket. Refer to Cruise Control Cable Replacement.





7. Remove the PCV valve hose assembly from the intake manifold and the valve rocker arm cover.





8. Disconnect the following electrical connectors:
^ The fuel meter body assembly connector (1)
^ The EVAP canister purge solenoid valve (2)
^ The Manifold Absolute Pressure (MAP) sensor (3)





9. Disconnect the following electrical connectors:
^ The Throttle Position (TP) sensor (1)
^ The Idle Air Control (IAC) motor (2)
^ The Engine Coolant Temperature (ECT) gauge sensor (3)
^ The A/C high pressure switch (4), if equipped





10. Remove the engine wiring harness bracket from the intake manifold stud.
11. Move and secure the engine wiring harness out of the way.





12. Disconnect the A/C vacuum hose from the intake manifold.
13. Remove the power brake booster vacuum hose bracket and nut from the intake manifold stud.
14. Disconnect the power brake booster vacuum hose from the intake manifold.





15. Remove the accelerator control cable bracket from the throttle body and the intake manifold.
16. Remove the EVAP canister purge solenoid. Refer to Evaporative Emission (EVAP) Canister Purge Solenoid Valve Replacement.
17. Remove the fuel lines from the fuel meter body assembly. Refer to Fuel Hose/Pipes Replacement (Engine Compartment).
18. Remove the distributor cap. Refer to Distributor Replacement.
19. Remove the ignition control module. Refer to Ignition Coil and ICM Replacement.





20. Remove the studs for the upper intake manifold.
21. Remove the upper intake manifold.





22. Remove the upper intake manifold gasket from the groove.
23. Discard the gasket.





24. Remove the seal from the fuel meter body assembly.
25. Discard the seal.

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

26. Clean all sealing surfaces and the inside of the upper intake manifold with a shop towel and cleaning solvent.
27. 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





28. If replacing the upper intake manifold, turn and remove the power brake booster vacuum tube fining from the upper intake manifold.
29. Remove and discard the seal.





30. If replacing the upper intake manifold, turn and remove the PCV valve cover from the upper intake manifold.
31. Remove and discard the seal.
32. Remove the throttle body if replacing the upper intake manifold. Refer to Throttle Body Assembly Replacement.
33. 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 distributor cap. Refer to Distributor Replacement.
13. Install the ignition control module. Refer to Ignition God and ICM Replacement.
14. Install the EVAP canister purge solenoid valve. Refer to Evaporative Emission (EVAP) Canister Purge Solenoid Valve Replacement.





15. Install the accelerator control cable bracket, studs, and nuts to the intake manifold and the throttle body.
^ Tighten the accelerator control cable bracket nuts and studs to 12 Nm (106 inch lbs.).





16. Connect the A/C vacuum hose to the intake manifold.
17. Install the power brake booster vacuum hose bracket and nut to the intake manifold stud.
^ Tighten the power brake booster vacuum hose bracket nut to 11 Nm (97 inch lbs.).
18. Connect the power brake booster vacuum hose to the intake manifold.





19. Install the bracket for the engine wiring harness on the lower intake manifold stud.
20. Install the engine wiring harness bracket nut.
^ Tighten the engine wiring harness bracket nut to 12 Nm (106 inch lbs.).





21. Connect the following electrical connectors:
^ The fuel meter body assembly connector (1)
^ The EVAP canister purge solenoid valve (2)
^ The Manifold Absolute Pressure (MAP) sensor (3)





22. Connect the following electrical connectors:
^ The Throttle Position (TP) sensor (1)
^ The Idle Air Control (IAC) motor (2)
^ The Engine Coolant Temperature (ECT) gauge sensor (3)
^ The A/C high pressure switch (4), if equipped





23. Connect the PCV valve hose assembly to the intake manifold and the valve rocker arm cover.
24. Install the cruise control cable, if equipped to the throttle shaft and the accelerator control cable bracket. Refer to Cruise Control Cable Replacement.
25. Install the accelerator control cable to the throttle shaft and the accelerator control cable bracket. Refer to Accelerator Controls Cable Replacement.
26. Install the air cleaner outlet duct to the throttle body assembly. Refer to Air Cleaner Outlet Duct Replacement.
27. Connect the PCV tube to the air cleaner outlet duct.
28. Install the air cleaner. Refer to Air Cleaner Assembly Replacement.
29. Install the engine cover. Refer to Engine Cover Replacement.