Intake Manifold Replacement UpperIntake Manifold

1. Disconnect the battery negative cable from the battery. Refer to Battery Negative Cable Disconnection and Connection in Engine Electrical.
2. Remove the Engine Cover. Refer to Engine Cover Replacement in Interior Trim.
3. Remove the air intake duct from the throttle body. Refer to Air Cleaner Assembly Replacement in Engine Controls.
4. Remove the air cleaner assembly from vehicle. Refer to Air Cleaner Assembly Replacement in Engine Controls.



5. Remove the crankcase vent tube from the throttle body.



6. Remove the PCV valve from the valve rocker arm cover.



7. Remove the EGR pipe from the upper intake manifold. Refer to Exhaust Gas Recirculation Pipe Replacement in Engine Controls.
8. Remove the ignition coil from the intake manifold. Refer to Ignition Coil and Ignition Coil Module Replacement .
9. Remove the throttle body from the upper intake manifold. Refer to Throttle Body Assembly Replacement in Engine Mechanical.
10. Remove the EVAP canister solenoid valve. Refer to Evaporative Emission Canister Purge Solenoid Valve Replacement in Engine Controls.
11. Remove the number 8 spark plug wire from the distributor. Refer to Spark Plug Wire Harness Replacement in Engine Electrical.



12. Remove the upper intake manifold bolts.
13. Remove the upper intake manifold and gaskets from the lower intake manifold.
14. Clean the excessive carbon deposit from the exhaust and the EGR valve passages.

1. Install the upper intake manifold and gaskets to the lower intake manifold.

Important: Failure to follow the procedure listed, could cause a driveability problem.

2. Coat a minimum of eight threads of the bolts with thread locking sealant G/M P/N 12345493.




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.

3. Install the upper intake manifold bolts and tighten in the following manner.

Tighten

•	Tighten the bolts in sequence to 8 N·m (72 lb in).

•	Re tighten the bolts in sequence to 18 N·m (13 lb ft).

4. Install the number 8 spark plug wire. Refer to Spark Plug Wire Harness Replacement in Engine Electrical.
5. Install the ignition coil to the upper intake manifold. Refer to Ignition Coil and Ignition Coil Module Replacement .
6. Install the EGR valve if necessary. Refer to Exhaust Gas Recirculation Valve Replacement in Engine Controls.



7. Install the EGR pipe to the upper intake manifold. Refer to Exhaust Gas Recirculation Pipe Replacement in Engine Controls.

Tighten
Tighten EGR valve fittings to 60 N·m (46 lb ft).

8. Install the EVAP canister solenoid valve to the intake manifold. Refer to Evaporative Emission Canister Purge Solenoid Valve Replacement in Engine Controls.
9. Install the throttle body to the upper intake manifold. Refer to Throttle Body Assembly Replacement in Engine Controls.



10. Install the PCV valve to the valve rocker arm cover to the cylinder head.



11. Install the crankcase vent tube to the valve rocker arm cover.
12. Install the air intake duct to the throttle body. Refer to Air Cleaner Assembly Replacement in Engine Controls -7.4L.
13. Connect the battery negative cables to the battery. Refer to Battery Negative Cable Disconnection and Connection in Engine Electrical.
14. Install Engine Cover. Refer to Engine Cover Replacement .

Intake Manifold Replacement LowerIntake Manifold

1. Remove the engine cover from the vehicle. Refer to Engine Cover Replacement in Interior Trim.
2. Drain the cooling system. Refer to Cooling System Draining and Filling in Engine Cooling.
3. Disconnect the battery negative cable from the battery. Refer to Battery Negative Cable Disconnection and Connection in engine electrical.
4. Remove the upper intake manifold from the lower intake manifold. Refer to Intake Manifold Replacement .
5. Remove the suction line from Air Conditioning from the A/C compressor. Refer to Compressor Hose Assembly Replacement in HVAC.

Important: Mark the relationship of the distributor housing to the rotor for proper reinstallation.

6. Remove the distributor from the lower intake manifold. Refer to Distributor Replacement .
7. Remove the MAP sensor from the lower intake manifold.



8. Remove the radiator hose from the thermostat. Refer to Radiator Hose Replacement in Engine Cooling.
9. Remove the thermostat housing from the lower intake manifold from the engine block. Refer to Engine Coolant Thermostat Replacement in Engine Cooling.
10. Remove the heater hoses from the heater core. Refer to Heater Hoses Replacement in Engine Cooling.
11. Remove the coolant bypass hose from the lower intake manifold and the water pump.
12. Remove the retaining bolts for the fuel rail. Refer to Fuel Hose/Pipes Replacement - Engine Compartment in Engine Controls.
13. Remove the fuel rail from the lower intake manifold. Refer to Fuel Hose/Pipes Replacement - Engine Compartment in Engine Controls.



14. Remove the lower intake manifold bolts from the engine head.
15. Remove the lower intake manifold from the cylinder head.
16. Remove the lower intake manifold gaskets and seals from the cylinder head.
17. Clean all sealing surfaces of oil and grease. Refer to Intake Manifold Cleaning and Inspection .

1. Install the lower intake manifold gaskets to the cylinder head with THIS SIDE UP stamped facing up.
2. Install the lower intake manifold to the engine block.
3. Apply the LOCTITE® 242 GM P/N 12345382 to the lower 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.

4. Install the lower intake manifold bolts to the engine head.

Tighten
Tighten the bolts in sequence to 30 N·m (22 lb ft).

Re-tighten the bolts in sequence to 40 N·m (30 lb ft).

5. Install the fuel rail to the lower intake manifold. Refer to Fuel Hose/Pipes Replacement - Engine Compartment in Engine Controls.
6. Install the fuel rail retaining bolts. Refer to Fuel Hose/Pipes Replacement - Engine Compartment in Engine Controls.
7. Install the coolant bypass hose to the water pump.
8. Install the heater hoses to the lower intake manifold. Refer to Heater Hoses Replacement in Engine Cooling.
9. Install the thermostat housing to the lower intake manifold from the engine block. Refer to Engine Coolant Thermostat Replacement in Engine Cooling.



10. Install the MAP sensor to the lower intake manifold.
11. Install the radiator hose to the thermostat housing. Refer to Radiator Hose Replacement in Engine Cooling.
12. Install the distributor to the engine block. Refer to Distributor Replacement in Engine Electrical.
13. Install the suction hose to the A/C compressor. Refer to Compressor Hose Assembly Replacement in HVAC.



14. Install the upper intake manifold to the lower intake manifold. Refer to Intake Manifold Replacement .
15. Install the discharge line to the A/C compressor. Refer to Compressor Hose Assembly Replacement in HVAC.
16. Refill the cooling system. Refer to Cooling System Draining and Filling in Engine Cooling.
17. Connect the battery negative cable to the battery. Refer to Battery Negative Cable Disconnection and Connection in Engine Electrical.
18. Install Engine Cover. Refer to Engine Cover Replacement .