Upper Intake Manifold Replacement

Intake Manifold Replacement - Upper

Removal Procedure

Caution Refer to Battery Disconnect Caution in Service Precautions.





1. Disconnect the negative battery cable.
2. Remove the fuel injector sight shield.
3. Disconnect the intake air temperature (IAT) sensor electrical connector.
4. Remove the air inlet duct from the throttle body.
5. Drain the cooling system.
6. Remove the right spark plug wires from the ignition control module and reposition.
7. Relieve the fuel pressure.
8. Remove the fuel rail assembly.
9. Remove the brake booster hose from the vacuum source manifold.
10. Remove the exhaust gas recirculation (EGR) valve wiring harness heat shield nut, bolt and the EGR heat shield.
11. Remove the throttle body support bracket upper bolt.





12. Disconnect the electrical connectors from the following:
- The EVAP purge solenoid
- The throttle position (T/P) sensor
- Idle air control (IAC) valve
- The manifold absolute pressure (MAP) sensor
- The mass air flow (MAP) sensor
13. Remove the EVAP purge solenoid vacuum line from the throttle body.
14. Remove the accelerator and the cruise control cables with the bracket from the throttle body.





15. Remove the upper intake manifold bolts and stud.
16. Clean the upper intake manifold bolt threads.
17. Remove the upper intake manifold by lifting the back of the intake and sliding the manifold forward from the throttle body support bracket.





18. Remove the upper-to-lower intake manifold carrier gasket from the upper intake manifold.
19. If the upper intake manifold is being replaced, remove the following:
- The throttle body.
- The manifold absolute pressure (MAP) sensor.
- The positive crankcase ventilation (PCV) valve.
- The vacuum source manifold.

Installation Procedure





1. If the manifold was replaced install the following:
- The vacuum source manifold.
- The positive crankcase ventilation (PCV) valve.
- The manifold absolute pressure (MAP) sensor. The throttle body.
2. Install the upper-to-lower intake manifold carrier gasket to the upper intake manifold.





3. Carefully place the upper intake manifold onto the lower intake manifold. Ensure that the alignment pins in the upper intake manifold align with the holes in the lower intake manifold.
4. Install the upper intake manifold.
5. Apply thread lock compound GM P/N 12345382 or equivalent, to the bolt threads before assembly.

Notice: Refer to Fastener Notice in Service Precautions.





6. Install the upper intake manifold bolts (1-10).
- Tighten the upper intake manifold bolts in sequence to 10 Nm (89 inch lbs.).
7. Install the accelerator and the cruise control cables with the bracket to the throttle body.
8. Install the EVAP purge solenoid vacuum line to the throttle body.





9. Connect the electrical connectors to the following:
- The mass air flow (MAF) sensor
- The manifold absolute pressure (MAP) sensor
- Idle air control (IAC) valve
- The throttle position (T/P) sensor
- The EVAP purge solenoid
10. Install the throttle body upper support bracket bolt.
- Tighten the throttle body support bracket bolts to 10 Nm (89 inch lbs.).





11. Install the EGR valve wiring harness heat shield, nut and bolt.
- Tighten the EGR valve wiring harness heat shield nut and bolt to 10 Nm (89 inch lbs.).
12. Install the brake booster hose to the vacuum source manifold.
13. Install the fuel rail assembly.
14. Install the right spark plug wires to the ignition control module.
15. Install the air inlet duct to the throttle body.
16. Connect the intake air temperature (IAT) sensor electrical connector.
17. Install the fuel injector sight shield.
18. Fill the cooling system.
19. Connect the negative battery cable.
20. Inspect for fluid or vacuum leaks.