GM Service Manual Online
For 1990-2009 cars only
Makes 🢒 Generic 🢒 2002 🢒 Unit Repair 🢒 Engine 🢒 Engine Mechanical - 3.0L (LW9) 🢒 Lower Intake Manifold Installation

    Object Number: 54281 Size: SH
  1. Apply sealer GM P/N United States 12378479, GM P/N Canada 10953472 or the equivalent at the engine block-to-lower intake manifold mating surface.

    2. Ensure that the bead meets the following conditions:

    • 2.0-3.0 mm (0.08-0.12 in) wide
    • 3.0-5.0 mm (0.12-0.20 in) thick
  2. Install the lower intake manifold.

    3. Object Number: 187067 Size: SH

    Notice: Failure to tighten vertical bolts before the diagonal bolts may cause an oil leak.

  3. Apply sealer GM P/N United States 12345382, GM P/N Canada 10953489 or the equivalent to the lower intake manifold bolt threads.

    4. 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.

    5. Tighten

    1. Tighten the lower intake manifold bolts in sequence to 7 N·m (62 lb in) on the first pass.
    2. Tighten the lower intake manifold bolts in sequence to 13 N·m (115 lb in) on the final pass.

    Object Number: 523326 Size: SH
  5. Install the heater inlet pipe.
  6. Install the heater inlet pipe nut.

    7. Tighten
    Tighten the heater inlet pipe nut to 25 N·m (18 lb ft).


    Object Number: 523321 Size: SH

    Important: Do not press on the fuel pressure regulator valve when installing the fuel injector rail assembly.

  7. Install the fuel injector rail assembly.
    8. 7.1. Install the fuel injector O-rings using GM P/N United States 12345616, GM P/N Canada 993182 or the equivalent.
    7.2. Install the injector nozzles into the lower intake manifold injector bores.
    7.3. Press on the injector rail using the palms of both hands until the injectors are fully seated.
  8. Install the fuel injector rail bolts.

    9. Tighten
    Tighten the fuel injector rail bolts to 10 N·m (89 lb in).


    Object Number: 187065 Size: SH
  9. Install the fuel feed and return pipe retaining clip.
  10. Install the fuel feed and return pipe retaining clip bolt.

    11. Tighten
    Tighten the fuel feed and return pipe retaining clip bolt to 8 N·m (71 lb in).