GM Service Manual Online
For 1990-2009 cars only

Intake Manifold Replacement Upper

Removal Procedure

  1. Disconnect the battery negative cable from the battery. Refer to Battery Cable in engine electrical.

  2. Object Number: 175670  Size: SH
  3. Remove the intake air resonator from the throttle body. Refer to Intake Air Resonator Replacement in Engine Controls - 7.4L.
  4. Remove the air cleaner intake duct from the throttle body. Refer to Air Air Cleaner Inlet Duct Replacement in Engine Controls - 7.4L.

  5. Object Number: 173189  Size: SH
  6. Remove the crankcase vent tube from the throttle body.

  7. Object Number: 173187  Size: SH
  8. Remove the PCV valve from the valve rocker arm cover.

  9. Object Number: 173284  Size: SH
  10. Remove the EGR pipe from the upper intake manifold. Refer to Exhaust Gas Recirculation Valve Replacement in Engine Controls - 7.4L.
  11. Remove Left and Right Side Secondary AIR Injection Pipe. If so Equipped. Refer to Secondary Air Injection Check Valve and Check Valve Pipe Replacement in Engine Controls - 7.4L.
  12. Remove the ignition coil from the intake manifold. Refer to Ignition Coil and Ignition Coil Module Replacement in Engine Electrical.
  13. Remove the throttle body from the upper intake manifold. Refer to Throttle Body Removal .
  14. Remove the EVAP canister solenoid valve. Refer to Evaporative Emission Canister Purge Solenoid Valve Replacement in Engine Controls - 7.4L.
  15. Remove the number 8 spark plug wire from the distributor.

  16. Object Number: 64529  Size: SH
  17. Remove the upper intake manifold bolts.
  18. Remove the upper intake manifold and gaskets.
  19. Clean the excessive carbon deposit from the exhaust and the EGR valve passages. Refer to Cylinder Head Clean and Inspect .

Installation Procedure


    Object Number: 64529  Size: SH
  1. Install the upper intake manifold gaskets.
  2. Install the upper intake manifold.
  3. Important: Failure to follow the procedure listed, could cause a driveability problem.

  4. Coat a minimum of eight threads of the bolts with thread locking sealant.
  5. Notice: Refer to Fastener Notice in the Preface section.


    Object Number: 67778  Size: SH
  6. Install the upper intake manifold bolts.
  7. Tighten

    1. Tighten the bolts in sequence to 8 N·m (71 lb in).
    2. Retighten the bolts in sequence to 8 N·m (13 lb ft).
  8. Install the number 8 spark plug wire.
  9. Install the ignition coil to the upper intake manifold. Refer to Ignition Coil and Ignition Coil Module Replacement in Engine Electrical.
  10. Install the EGR valve if necessary. Refer to Exhaust Gas Recirculation Valve Replacement in Engine Controls - 7.4L.

  11. Object Number: 173284  Size: SH
  12. Install the EGR pipe to the upper intake manifold.
  13. Tighten
    Tighten EGR valve fittings to 60 N·m (46 lb ft).

  14. Install Left and Right Side Secondary AIR Injection Pipes. If so equipped. Refer to Secondary Air Injection Check Valve and Check Valve Pipe Replacement in Engine Controls - 7.4L.
  15. Install the EVAP canister solenoid valve to the intake manifold. Refer to Evaporative Emission Canister Purge Solenoid Valve Replacement in Engine Controls - 7.4L.
  16. Install the throttle body to the upper intake manifold. Refer to Throttle Body Assembly Replacement .

  17. Object Number: 173187  Size: SH
  18. Install the PCV valve to the valve rocker arm cover to the cylinder head. 

  19. Object Number: 173189  Size: SH
  20. Install the crankcase vent tube to the valve rocker arm cover.
  21. Install the air cleaner intake duct to the throttle body. Refer to Air Cleaner Inlet Duct Replacement in Engine Controls - 7.4L.
  22. Install the intake air resonator to the throttle body. Refer to Intake Air Resonator Replacement in Engine Controls - 7.4L.
  23. Connect the battery negative cables to the battery. Refer to Battery Cable in Engine Electrical.

Intake Manifold Replacement Lower

Removal Procedure

Important: The lower intake manifold gaskets and seals are reusable. Replace only the gaskets and seals if they are damaged.

  1. Drain the cooling system. Refer to Cooling System Draining and Filling in Engine Cooling.
  2. Disconnect the battery negative cable from the battery. Refer to Battery Cable in engine electrical.
  3. Remove the upper intake manifold from the lower intake manifold. Refer to Intake Manifold Removal .
  4. Remove the suction line from Air Conditioning from the A/C compressor. Refer to Compressor Hose Assembly Replacement in HVAC.
  5. Remove the distributor from the lower intake manifold. Refer to Distributor Replacement in engine electrical.
  6. Remove the MAP sensor from the lower intake manifold. Refer to Manifold Absolute Pressure Sensor Replacement in Engine Controls.
  7. Remove the radiator hose from the thermostat. Refer to Radiator Hose Replacement in Engine Cooling.
  8. Remove the thermostat housing from the lower intake manifold from the engine block. Refer to Engine Coolant Thermostat Replacement in Engine Cooling.
  9. Remove the heater hoses from the heater core. Refer to Heater Core Replacement in Engine Cooling.
  10. Remove the coolant bypass hose from the lower intake manifold and the water pump.
  11. Remove the retaining bolts for the fuel rail. Refer to Fuel Injection Fuel Rail Assembly Replacement in Engine Controls.
  12. Remove the fuel rail from the lower intake manifold. Refer to Fuel Injection Fuel Rail Assembly Replacement in Engine Controls.

  13. Object Number: 64532  Size: SH
  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 Clean and Inspect (Lower) .

Installation Procedure


    Object Number: 64532  Size: SH
  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 bolt thread locking material to the lower intake manifold bolts.

  4. Object Number: 67780  Size: SH

    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.

  5. Install the lower intake manifold bolts to the engine head.
  6. 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).

  7. Install the fuel rail to the lower intake manifold. Refer to Fuel Injection Fuel Rail Assembly Replacement in Engine Controls.
  8. Install the fuel rail retaining bolts. Refer to Fuel Injection Fuel Rail Assembly Replacement in Engine Controls.
  9. Install the coolant bypass hose to the water pump.
  10. Install the heater hoses to the lower intake manifold. Refer to Heater Hoses Replacement in Engine Cooling.
  11. Install the thermostat housing to the lower intake manifold from the engine block. Refer to Engine Coolant Thermostat Replacement in Engine Cooling.

  12. Object Number: 19673  Size: SH
  13. Install the MAP sensor to the lower intake manifold. Refer to Manifold Absolute Pressure Sensor Replacement in Engine Controls.
  14. Install the radiator hose to the thermostat housing. Refer to Radiator Hose Replacement in Engine Cooling.
  15. Install the distributor to the engine block. Refer to Distributor Replacement .
  16. Install the suction hose to the A/C compressor. Refer to Compressor Hose Assembly Replacement in HVAC.
  17. Install the upper intake manifold to the lower intake manifold. Refer to Intake Manifold Installation .
  18. Install the discharge line to the A/C compressor. Refer to Compressor Hose Assembly Replacement in HVAC.
  19. Refill the cooling system. Refer to Cooling System Draining and Filling in Engine Cooling.
  20. Connect the battery negative cable to the battery. Refer to Battery Cable in Engine Electrical.