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. Unsnap the intake manifold sight shield from the stud.
4. Remove the sight shield from the bracket.
5. Remove the sight shield bracket nuts (1) and bracket, if necessary.
6. Relieve the fuel system pressure. Refer to Fuel Pressure Relief in Engine Controls - 8.1L.
7. Disconnect the fuel feed and return pipes. Refer to Metal Collar Quick Connect Fitting Service in Engine Controls - 8.1L.



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 (MAF) sensor (3)

11. Reposition the 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

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 (3) at the EGR adapter.
21. Reposition the EGR pipe (2).
22. Remove and discard the EGR valve pipe gasket (1).



23. Disconnect the evaporative emission (EVAP) tube from the purge solenoid.



24. Unclip the EVAP tube from the fuel rail.
25. Disconnect the EVAP tube from the vent pipe at the rear of the engine.
26. Remove the EVAP tube.



27. Remove the fuel pressure regulator vacuum hose.



28. If replacing the intake manifold, remove the fuel rail studs.
29. Remove the fuel rail.




Important: Do not attempt to loosen the manifold by prying under the gasket surface with any tool.

30. Remove the intake manifold bolts.



31. Remove the intake manifold.




Important: The intake manifold gaskets are not reusable.

32. Remove and discard the intake manifold side gaskets.



33. 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.

34. Remove the splash shield.
35. If replacing the intake manifold, refer to Intake Manifold Disassemble .
36. Clean and inspect the intake manifold. Refer to Intake Manifold Cleaning and Inspection .

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 the NEW intake manifold end seals.



5. Install the NEW intake manifold side gaskets.



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.



9. Apply threadlock, GM P/N 12345382 (Canadian P/N 10953489), or equivalent to a minimum of eight threads of the intake manifold bolts.
10. Install the intake manifold bolts.




Notice: Use the correct fastener in the correct location. Replacement fasteners must be the correct part number for that application. Fasteners requiring replacement or fasteners requiring the use of thread locking compound or sealant are identified in the service procedure. Do not use paints, lubricants, or corrosion inhibitors on fasteners or fastener joint surfaces unless specified. These coatings affect fastener torque and joint clamping force and may damage the fastener. Use the correct tightening sequence and specifications when installing fasteners in order to avoid damage to parts and systems.

11. Tighten the intake manifold bolts in the sequence shown, using four passes.

Tighten

1. Tighten the bolts a first pass to 5 N·m (44 lb in).
2. Tighten the bolts a second pass to 8 N·m (71 lb in).
3. Tighten the bolts a final pass to 12 N·m (106 lb in).




Important: Lubricate the fuel injector O-ring seals with clean engine oil and install onto the spray tip of each injector.

12. If replacing the intake manifold, install the fuel rail.
13. Install the fuel rail studs.

Tighten
Tighten the studs to 12 N·m (106 lb in).




14. Install the fuel pressure regulator vacuum hose.



15. Install the EVAP tube.
16. Connect the EVAP tube to the vent pipe at the rear of the engine.
17. Clip the EVAP tube to the fuel rail.



18. Connect the EVAP tube to the purge solenoid.



19. Install a NEW EGR valve pipe gasket (1).
20. Position the EGR pipe (2).
21. Install the EGR pipe bolts (3) at the EGR adapter.

Tighten
Tighten the bolts to 25 N·m (18 lb ft).




22. Connect the EGR valve electrical connector (1).



23. Install the bypass valve vacuum hose (1) to the intake manifold.



24. Position the engine harness over the engine compartment.
25. Connect the following electrical connectors:

•	Generator (1)

•	Injector harness (2)

•	Ignition coil harness (3)

•	TP sensor (4)

•

ETC (5)

•	Purge valve solenoid

26. Install the CPA retainer at the ignition coil harness.
27. Install the engine harness bolt and studs

Tighten

•	Tighten the bolt to 5 N·m (44 lb in).

•	Tighten the studs to 10 N·m (89 lb in).




28. Connect the following electrical connectors:

•	MAP sensor (1)

•	Ignition coil harness (2)

•	ECT sensor (3)

29. Install the CPA retainer at the ignition coil harness.



30. Position engine harness branch over the top of engine.
31. Connect the following electrical connectors:

•	Pressure cycling switch (1)

•	Surge tank switch (2)

•	MAF sensor (3)

32. Connect the engine harness clip to the wheelhouse splash shield.
33. Connect the engine harness clips to the studs on the front of dash.



34. Connect the fuel feed and return pipes.
35. Install the sight shield bracket and nuts (1).

Tighten
Tighten the nuts to 5 N·m (44 lb in).

36. Install the sight shield to the bracket.
37. Snap the intake manifold sight shield to the stud.



38. Install the air cleaner outlet duct.
39. Tighten the clamps at the throttle body and air cleaner.

Tighten
Tighten the clamps to 4 N·m (35 lb in).