Intake Manifold Replacement
Intake Manifold ReplacementRemoval 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. Loosen the clamps at the throttle body and air cleaner.
2. Remove the air cleaner outlet duct.
3. Loosen the intake manifold sight shield bolt (3).
4. Remove the sight shield from the bracket (1).
5. Remove the sight shield bracket (1) and nuts.
6. Relieve the fuel system pressure.
7. Disconnect the fuel feed and return pipes.
8. Disconnect the engine harness clips from the studs on the front of dash.
9. Disconnect the engine harness clip from the wheelhouse splash shield.
10. Disconnect the following electrical connectors:
- Pressure cycling switch (1)
- Surge tank switch (2)
- Mass airflow (MAP) sensor (3)
11. Reposition engine harness branch to top of engine.
12. Remove the connector position assurance (CPA) retainer at the ignition coil harness.
13. Disconnect the following electrical connectors:
- Manifold absolute pressure (MAP) sensor (1)
- Ignition coil harness (2)
- Engine coolant temperature (ECT) sensor (3)
14. Remove the engine harness bolt and studs
15. Remove the CPA retainer at the ignition coil harness.
16. Disconnect the following electrical connectors:
- Generator (1)
- Injector harness (2)
- Ignition coil harness (3)
- Throttle position (TP) sensor (4)
- Electronic throttle control (ETC) (5)
- Purge valve solenoid (6)
17. Reposition the engine harness to the drivers side of the engine compartment.
18. Remove the bypass valve vacuum hose (1) from the intake manifold.
19. Disconnect the exhaust gas recirculation (EGR) valve electrical connector (1).
20. Remove the EGR pipe bolts at the EGR adapter.
21. Reposition the EGR pipe.
22. Remove and discard the EGR valve pipe gasket.
23. Remove the fuel pressure regulator vacuum hose.
24. If replacing the intake manifold, remove the fuel rail studs.
25. Remove the fuel rail.
26. Remove the intake manifold bolts.
Important: Do not attempt to loosen the manifold by prying under the gasket surface with any tool.
27. Remove the intake manifold.
Important: The intake manifold gaskets are not reusable.
28. Remove and discard the intake manifold side gaskets.
29. Remove and discard the intake manifold end seals.
Important: The splash shield is secured using a snap-in fit. Do not distort the splash shield. The splash shield is reusable.
30. Remove the splash shield.
31. If replacing the intake manifold, refer to Intake Manifold Disassemble.
32. Clean and inspect the intake manifold.
Installation Procedure
1. If replacing the intake manifold, refer to Intake Manifold Assemble.
2. Install the splash shield.
3. Ensure the splash shield (2) snap fits between the cylinder heads (1).
4. Install NEW intake manifold end seals.
5. Install NEW intake manifold side gaskets onto the cylinder heads.
6. Ensure the intake manifold gasket tabs align with the hole in the head gasket.
7. Ensure the intake manifold gasket tabs align with the slot in the intake manifold end seals.
8. Install the intake manifold gaskets to the cylinder head with THIS SIDE UP stamped facing up.
9. Install the intake manifold.
Intake Manifold Tightening Sequence:
10. Apply threadlock, GM U.S. P/N 12345382, Canada P/N 10953489, or equivalent to a minimum of eight threads of the intake manifold bolts.
11. Install the intake manifold bolts.
Notice: Refer to Fastener Notice in Service Precautions.
12. Tighten the intake manifold bolts in sequence shown, using four passes.
12.1. Tighten the intake manifold bolts to 5 Nm (44 inch lbs.) on the first pass.
12.2. Tighten the intake manifold bolts to 5 Nm (44 inch lbs.) on the second pass.
Inspect the intake manifold joints for signs of intake manifold shifting. Correct as required.
12.3. Tighten the intake manifold bolts to 10 Nm (89 inch lbs.) on the third pass.
12.4. Tighten the intake manifold bolts to 12 Nm (106 inch lbs.) on the final pass.
Important: Lubricate the fuel injector O-ring seals with clean engine oil and install onto the spray tip of each injector.
13. If replacing the intake manifold, install the fuel rail.
14. Install the fuel rail studs.
- Tighten the fuel rail studs to 12 Nm (106 inch lbs.).
15. Install the fuel pressure regulator vacuum hose.
16. Install a NEW EGR valve pipe gasket.
17. Position the EGR pipe.
18. Install the EGR pipe bolts at the EGR adapter.
- Tighten the EGR pipe bolts to 30 Nm (22 ft. lbs.).
19. Connect the EGR valve electrical connector (1).
20. Install the bypass valve vacuum hose (1) to the intake manifold.
21. Position the engine harness over the engine compartment.
22. Connect the following electrical connectors:
- Generator(1)
- Injector harness (2)
- Ignition coil harness (3)
- TP sensor (4)
- ETC (5)
- Purge valve solenoid (6)
23. Install the CPA retainer at the ignition coil harness.
24. Install the engine harness bolt and studs.
- Tighten the engine harness bolt to 5 Nm (44 inch lbs.).
- Tighten the engine harness stud to 10 Nm (89 inch lbs.).
25. Connect the following electrical connectors:
- MAP sensor (1)
- Ignition coil harness (2)
- ECT sensor (3)
26. Install the CPA retainer at the ignition coil harness.
27. Position engine harness branch over the top engine
28. Connect the following electrical connectors:
- Pressure cycling switch (1)
- Surge Tank switch (2)
- MAF sensor (3)
29. Connect the engine harness clip to the wheelhouse splash shield.
30. Connect the engine harness clips to the studs on the front of dash.
31. Connect the fuel feed and return pipes.
32. Install the sight shield bracket (1) and nuts.
- Tighten the sight shield bracket nuts to 5 N-m (44 in.lb).
33. Install the sight shield to the bracket (1).
34. Tighten the intake manifold sight shield bolt (3).
- Tighten the intake manifold sight shield bolt to 10 N-m (89 in.lbs.).
35. Install the air cleaner outlet duct.
36. Tighten the clamps at the throttle body and air cleaner.
- Tighten the air cleaner outlet duct clamp to 4N-m (35 in. lbs.).