GM Service Manual Online
For 1990-2009 cars only
Makes 🢒 GMC_Truck 🢒 2003 🢒 Sonoma Pickup - 2WD 🢒 Engine 🢒 Engine Electrical 🢒 Valve Rocker Arm Cover Replacement

Removal Procedure

    Object Number: 346145 Size: SH
  1. Drain the cooling system. Refer to Cooling System Draining and Filling .
  2. Disconnect the power brake booster vacuum hose.
  3. Remove the air cleaner outlet resonator. Refer to Air Cleaner Outlet Resonator Replacement for the 2.2L (LN2) engine.
  4. Remove the throttle body. Refer to Throttle Body Assembly Replacement for the 2.2L (LN2) engine.

    5. Object Number: 382647 Size: SH
  5. Remove the spark plug wire harness retainer from the thermostat assembly.
  6. Remove the spark plug wires from the spark plugs. Refer to Spark Plug Wire Replacement for the 2.2L (LN2) engine.
  7. Disconnect the radiator and heater inlet hoses from the water outlet adapter.

    8. Object Number: 175491 Size: SH

    Important: Do not bend the water outlet adapter pipe out of the way in order to remove the valve rocker arm cover.

  8. Remove the water outlet adapter.

    9. Object Number: 565513 Size: SH
  9. Disconnect the fuel injector harness electrical connector.
  10. Remove the fuel injector harness electrical connector from the bracket on the valve rocker arm cover.
  11. Remove the engine wiring harness from the bracket.
  12. Move and secure the engine wiring harness out of the way.

    13. Object Number: 349613 Size: SH
  13. Remove the engine wiring harness bracket at the rear of the engine using the following procedure:
    14. 13.1. Loosen the bolt at the rear of the cylinder head.
    13.2. Remove the 2 bolts that secure the bracket to the valve rocker arm cover.
    13.3. Slide the bracket off of the bolt at the rear of the cylinder head.

    Object Number: 511992 Size: SH
  14. Remove the air cleaner outlet resonator bracket.

    15. Object Number: 500536 Size: SH

    Important: The valve rocker arm cover gasket is reusable. Only replace the valve rocker arm cover gasket if it is damaged.

  15. Remove the rocker arm cover bolts, stud (1) and bracket (2).
  16. Remove the rocker arm cover.
  17. Remove the rocker arm cover gasket.
  18. Clean all sealing surfaces and the valve rocker arm cover.

Installation Procedure

    Object Number: 500536 Size: SH
  1. Install a new rocker arm cover gasket in the groove around the rocker arm cover, if the old gasket was removed.
  2. Install the rocker arm cover to the cylinder head.
  3. Install the rocker arm cover bolts, stud (1) and bracket (2).

    4. Notice: Refer to Fastener Notice in the Preface section.


    Object Number: 500535 Size: SH
  4. Install the rocker arm cover bolts in sequence (1-8).

    5. Tighten
    Tighten the rocker arm cover bolts to 10 N·m (89 lb in).


    Object Number: 511992 Size: SH
  5. Install the air cleaner outlet resonator bracket and bolts.

    6. Tighten
    Tighten the air cleaner outlet resonator bracket bolts to 10 N·m (89 lb in).


    Object Number: 349613 Size: SH
  6. Install the wiring harness bracket to the rear of the engine by using the following procedure:
    7. 6.1. Slide the bracket over the bolt at the rear of the cylinder head.
    6.2. Install the 2 bolts that secure the bracket to the valve rocker arm cover.
  7. Tighten the bolts in the following order:

    8. Tighten

    1. Tighten the 2 bolts to the valve rocker arm cover to 10 N·m (89 lb in).
    2. Tighten the bolt at the rear of the cylinder head to 25 N·m (18 lb ft).

    Object Number: 565513 Size: SH
  8. Position the engine wiring harness.
  9. Install the engine wiring harness to the bracket.
  10. Install the fuel injector harness electrical connector to the bracket on the valve rocker arm cover.
  11. Connect the fuel injector harness electrical connector.
  12. Install the water outlet adapter.

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

  13. Connect the radiator and heater inlet hoses to the water outlet adapter.
  14. Install the throttle body. Refer to Throttle Body Assembly Replacement for the 2.2L (LN2) engine.

    15. Object Number: 382647 Size: SH
  15. Install the spark plug wires to the spark plugs. Refer to Spark Plug Wire Replacement for the 2.2L (LN2) engine.
  16. Install the spark plug wire harness retainer to the thermostat assembly.
  17. Install the air cleaner outlet resonator. Refer to Air Cleaner Outlet Resonator Replacement for the 2.2L (LN2) engine.

    18. Object Number: 346145 Size: SH
  18. Connect the power brake booster vacuum hose.
  19. Fill the engine cooling system. Refer to Cooling System Draining and Filling .