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For 1990-2009 cars only
Makes 🢒 Chevrolet 🢒 1998 🢒 Astro - 4WD 🢒 Engine 🢒 Engine Electrical 🢒 Intake Manifold Replacement

Intake Manifold Replacement Upper

Removal Procedure
  1. Remove the engine cover. Refer to Engine Cover Replacement in Interior Trim.
  2. Remove the air cleaner outlet duct. Refer to Air Cleaner Outlet Duct Replacement in Engine Controls.

    3. Object Number: 163855 Size: SH
  3. Disconnect the following electrical connectors:
    4. • The A/C pressure switch, if equipped
    • The throttle position (TP) sensor
    • The idle air control (IAC) motor
    • The fuel meter body assembly connector
    • The manifold absolute pressure (MAP) sensor
    • The EVAP canister purge solenoid valve

    Object Number: 172995 Size: SH
  4. Remove the PCV valve hose assembly from the intake manifold and the valve rocker arm cover.
  5. Disconnect the vacuum hose from the intake manifold, if equipped with A/C.

    6. Object Number: 363396 Size: SH
  6. Remove the engine wiring harness bracket from the stud at the EVAP canister purge solenoid valve.
  7. Remove the EVAP canister purge solenoid. Refer to Evaporative Emission Canister Purge Solenoid Valve Replacement in Engine Controls.

    8. Object Number: 398027 Size: SH
  8. Disconnect the accelerator control cable from the throttle shaft. Refer to Accelerator Control Cable Replacement in Engine Controls.
  9. Disconnect the cruise control cable, if equipped. Refer to Cruise Control Cable Replacement in Cruise Control.
  10. Remove the bolt holding the transmission fluid filler tube to the accelerator control cable bracket.
  11. Remove the accelerator control cable bracket from the throttle body and the intake manifold.

    12. Object Number: 363391 Size: SH
  12. Remove the nut holding the A/C hose bracket, if equipped to the intake manifold stud.
  13. Remove the A/C hose bracket from the stud.
  14. Remove the nut holding the engine wiring harness bracket to the intake manifold stud.
  15. Remove the engine wiring harness bracket from the stud.
  16. Remove the fuel lines from the fuel meter body assembly. Refer to Fuel Hose/Pipes Replacement - Engine Compartment in Engine Controls.

    17. Object Number: 334513 Size: SH
  17. Remove the upper intake manifold. Refer to Intake Manifold Disassemble .
  18. Clean all sealing surfaces. Refer to Intake Manifold Cleaning and Inspection .

Installation Procedure

    Object Number: 31649 Size: SH
  1. Install the upper intake manifold. Refer to Intake Manifold Assemble .
  2. Install the fuel lines to the fuel meter body assembly. Refer to Fuel Hose/Pipes Replacement - Engine Compartment in Engine Controls.

    3. Object Number: 398027 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.

  3. Install the accelerator control cable bracket, studs, and nuts to the intake manifold and the throttle body.

    4. Tighten
    Tighten the accelerator control cable bracket nuts and studs to 12 N·m (106 lb in).

  4. Install the transmission fluid fill tube and bolt to the accelerator control cable bracket.

    5. Tighten
    Tighten the transmission fluid fill tube bolt 6 N·m (53 lb in).

  5. Install the cruise control cable, if equipped. Refer to Cruise Control Cable Replacement in Cruise Control.
  6. Install the accelerator control cable to the throttle shaft. Refer to Accelerator Control Cable Replacement in Engine Controls.

    7. Object Number: 363391 Size: SH
  7. Install the engine wiring harness bracket and nut to the intake manifold stud.

    8. Tighten
    Tighten the engine wiring harness bracket nut to 12 N·m (106 lb in).

  8. Install the A/C hose bracket and nut, if equipped to the intake manifold stud.

    9. Tighten
    Tighten the A/C hose bracket nut to 5 N·m (44 lb in).


    Object Number: 363396 Size: SH
  9. Install the EVAP canister purge solenoid valve. Refer to Evaporative Emission Canister Purge Solenoid Valve Replacement in Engine Controls.
  10. Install the engine wiring harness bracket and the nut onto the stud at the EVAP canister purge solenoid valve.

    11. Tighten
    Tighten the engine wiring harness bracket nut to 8 N·m (71 lb in).


    Object Number: 172995 Size: SH
  11. Connect the PCV valve hose assembly to the intake manifold and the valve rocker arm cover.
  12. Connect the vacuum hose to the intake manifold, if equipped with A/C.

    13. Object Number: 163855 Size: SH
  13. Connect the following electrical connectors:
    14. • The A/C pressure switch, if equipped
    • The throttle position (TP) sensor
    • The idle air control (IAC) motor
    • The fuel meter body assembly connector
    • The manifold absolute pressure (MAP) sensor
    • The EVAP canister purge solenoid valve
  14. Install the air cleaner outlet duct. Refer to Air Cleaner Outlet Duct Replacement in Engine Controls.
  15. Install the engine cover. Refer to Engine Cover Replacement in Interior Trim.

Intake Manifold Replacement Lower

Removal Procedure

    Object Number: 71614 Size: SH

    Caution: Unless directed otherwise, the ignition and start switch must be in the OFF or LOCK position, and all electrical loads must be OFF before servicing any electrical component. Disconnect the negative battery cable to prevent an electrical spark should a tool or equipment come in contact with an exposed electrical terminal. Failure to follow these precautions may result in personal injury and/or damage to the vehicle or its components.

  1. Disconnect the battery negative cable. Refer to Battery Replacement .
  2. Remove the engine cover. Refer to Engine Cover Replacement .
  3. Drain the cooling system. Refer to Cooling System Draining and Filling .
  4. Remove the air cleaner assembly. Refer to Air Cleaner Assembly Replacement .
  5. Remove the drive belt. Refer to Drive Belt Replacement .
  6. Remove the radiator inlet hose at the water outlet. Refer to Radiator Hose Replacement .
  7. Remove the heater hose from the intake manifold. Refer to Heater Water Bypass Valve Replacement .
  8. Remove the water pump inlet hose from the intake manifold.
  9. Remove the ground wire from the stud at the water outlet.

    10. Object Number: 398027 Size: SH
  10. Disconnect the accelerator control cable from the throttle shaft. Refer to Accelerator Control Cable Replacement .
  11. Disconnect the cruise control cable, if equipped. Refer to Cruise Control Cable Replacement .
  12. Remove the bolt holding the transmission fluid filler tube to the accelerator control cable bracket.
  13. Remove the accelerator control cable bracket from the throttle body and the intake manifold.

    14. Object Number: 163855 Size: SH
  14. Disconnect the following electrical connectors:
    15. • The fuel meter body assembly
    • The EVAP canister purge solenoid valve
    • The idle air control (IAC) motor
    • The throttle position (TP) sensor
    • The engine coolant temperature (ECT) gauge sensor
    • The A/C compressor high pressure switch, if equipped
    • The A/C clutch switch, if equipped
    • The exhaust gas recirculation (EGR) valve
    • The engine coolant temperature (ECT) sensor

    Object Number: 340090 Size: SH
  15. In order to remove the front intake manifold bolt, perform the following:
    16. 15.1. Remove the A/C compressor side brace.
    15.2. Loosen the nut for the power steering pump rear bracket.
    15.3. Remove the oil filler tube bracket bolt and the oil filler tube.
    15.4. Remove the bolts and the nut for the power steering pump mounting bracket.
    15.5. Leave the A/C compressor, if equipped, and the power steering pump on the bracket.
    15.6. Slide the power steering pump bracket forward to access the bolt at the front of the intake manifold.
  16. Remove the distributor. Refer to Distributor Replacement .

    17. Object Number: 172982 Size: SH
  17. Remove the exhaust gas recirculation (EGR) valve inlet pipe from the intake and the exhaust manifolds.
  18. Disconnect the fuel supply and the return pipes at the rear of the intake manifold. Refer to Fuel Hose/Pipes Replacement - Engine Compartment .

    19. Object Number: 172995 Size: SH
  19. Disconnect PCV valve hose assembly from the intake manifold and the valve rocker arm cover.
  20. Disconnect the vacuum hose from the intake manifold, if equipped with A/C.

    21. Object Number: 363391 Size: SH
  21. Remove the nut holding the A/C hose bracket to the intake manifold stud, if equipped.
  22. Remove the nut holding the engine wiring harness bracket to the intake manifold stud.
  23. Remove bolts holding the ignition control module (ICM) and set the ICM aside.

    24. Object Number: 363396 Size: SH
  24. Remove the nut and the engine wiring harness bracket from the stud at the EVAP canister purge solenoid valve.
  25. Remove the EVAP canister purge solenoid valve. Refer to Evaporative Emission Canister Purge Solenoid Valve Replacement .

    26. Object Number: 31510 Size: SH
  26. Remove the lower intake manifolds bolts.
  27. Remove the lower intake manifold. Refer to Intake Manifold Removal .
  28. Clean all sealing surfaces. Refer to Intake Manifold Cleaning and Inspection .

Installation Procedure

    Object Number: 31510 Size: SH
  1. Install the lower intake manifold. Refer to Intake Manifold Installation .

    2. Object Number: 363396 Size: SH
  2. Install the EVAP canister purge solenoid valve. Refer to Evaporative Emission Canister Purge Solenoid Valve Replacement .

    3. 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 nut and the engine wiring harness bracket to the stud for the EVAP canister purge solenoid valve.

    4. Tighten
    Tighten the engine wiring harness bracket nut to 8 N·m (71 lb in).

  4. Install the ICM. Refer to Ignition Coil and Ignition Coil Module Replacement .
  5. Install the fuel supply and return pipes to the rear of the intake manifold. Refer to Fuel Hose/Pipes Replacement - Engine Compartment .

    6. Object Number: 363391 Size: SH
  6. Install the nut and the engine wiring harness bracket to the intake manifold stud.

    7. Tighten
    Tighten the engine wiring harness bracket nut to 12 N·m (106 lb in).

  7. Install the nut and the A/C hose bracket to the intake manifold stud, if equipped.

    8. Tighten
    Tighten the A/C hose bracket nut to 5 N·m (44 lb in).


    Object Number: 172995 Size: SH
  8. Install the PCV valve hose assembly to the intake manifold and the valve rocker arm cover.
  9. Install the vacuum hose to the intake manifold, if equipped with A/C.

    10. Object Number: 172982 Size: SH
  10. Install the exhaust gas recirculation (EGR) valve inlet pipe to the intake and the exhaust manifolds.

    11. Tighten

        • Tighten the EGR valve inlet pipe intake manifold nut to 25 N·m (18 lb ft).
        • Tighten the EGR valve inlet pipe exhaust manifold nut to 30 N·m (22 lb ft).
        • Tighten the EGR valve inlet pipe clamp bolt to 25 N·m (18 lb ft).
  11. Install the distributor. Refer to Ignition Coil and Ignition Coil Module Replacement .

    12. Object Number: 340090 Size: SH
  12. Reposition the power steering pump mounting bracket.
  13. Install the power steering pump mounting bracket three bolts and the nut.

    14. Tighten
    Tighten the power steering pump mounting bracket bolts and the nut and the power steering pump rear bracket nut to 41 N·m (30 lb ft).

  14. Install A/C compressor side brace and bolts.

    15. Tighten

    1. Tighten the A/C compressor side brace bolt to 50 N·m (37 lb ft)
    2. Tighten the side brace bolt to the generator bracket to 25 N·m (18 lb ft).
  15. Install the oil filler tube and bolt.

    16. Tighten
    Tighten the oil filler tube bolt to 25 N·m (18 lb ft).

  16. Install the ground wire and the nut to the water outlet stud.

    17. Tighten
    Tighten the ground wire nut to 10 N·m (88 lb in).


    Object Number: 163855 Size: SH
  17. Connect the following electrical connectors:
    18. • The fuel meter body assembly
    • The EVAP canister purge solenoid valve
    • The idle air control (IAC) motor
    • The throttle position (TP) sensor
    • The engine coolant temperature (ECT) gauge sensor
    • The A/C compressor high pressure switch
    • The A/C clutch switch
    • The exhaust gas recirculation (EGR) valve
    • The engine coolant temperature (ECT) sensor

    Object Number: 216754 Size: SH
  18. Install the accelerator control cable bracket, studs, and nuts to the intake manifold and the throttle body.

    19. Tighten
    Tighten the accelerator control cable bracket nuts and studs to 12 N·m (106 lb in).

  19. Install the transmission fluid fill tube and bolt to the accelerator control cable bracket.

    20. Tighten
    Tighten the transmission fluid fill tube bolt 6 N·m (53 lb in).

  20. Install the cruise control cable, if equipped. Refer to Cruise Control Cable Replacement .
  21. Install the accelerator control cable to the throttle shaft. Refer to Accelerator Control Cable Replacement .

    22. Object Number: 71614 Size: SH
  22. Install the water pump inlet hose to the intake manifold.
  23. Install the heater hoses. Refer to Heater Water Bypass Valve Replacement .
  24. Install the radiator inlet hose to the water outlet. Refer to Radiator Hose Replacement .
  25. Install the drive belt. Refer to. Drive Belt Replacement .
  26. Refill the cooling system. Refer to Cooling System Draining and Filling .
  27. Install the air cleaner assembly. Refer to Air Cleaner Assembly Replacement .
  28. Connect the battery negative cable. Refer to Battery Replacement .
  29. Install the engine cover. Refer to Engine Cover Replacement .