GM Service Manual Online
For 1990-2009 cars only
Makes 🢒 Oldsmobile 🢒 2001 🢒 Aurora 🢒 Engine 🢒 Engine Controls - 4.0L 🢒 Fuel Injection Fuel Rail Assembly Replacement

Removal Procedure

    Notice: 

       • Use care when servicing the fuel system components, especially the fuel injector electrical connectors, the fuel injector tips, and the injector O-rings. Plug the inlet and the outlet ports of the fuel rail in order to prevent contamination.
       • Do not use compressed air to clean the fuel rail assembly as this may damage the fuel rail components.
       • Do not immerse the fuel rail assembly in a solvent bath in order to prevent damage to the fuel rail assembly.


    Object Number: 575657 Size: SH
  1. Relieve the fuel system pressure. Refer to the Fuel Pressure Relief .
  2. Clean the fuel rail assembly with a spray type engine cleaner, GM X-30A or equivalent, if necessary. Follow the package instructions.
  3. Disconnect the fuel feed and return pipes (2, 3) from the fuel rail. Refer to Metal Collar Quick Connect Fitting Service .

    4. Object Number: 522641 Size: SH
  4. Disconnect the fuel pressure regulator vacuum hose.

    5. Object Number: 522644 Size: SH
  5. Disconnect the positive crankcase ventilation (PCV) air tube from the cam cover.

    6. Object Number: 490597 Size: SH
  6. Disconnect the PCV valve (1) from the cam cover.
  7. Reposition the coolant surge tank inlet pipe. Refer to Surge Tank Pipe Replacement - Inlet in Engine Cooling.

    8. Object Number: 522654 Size: SH
  8. Remove the fuel rail bracket retainer nut.

    9. Object Number: 490817 Size: SH
  9. Disconnect the fuel injector electrical connectors (1) from each fuel injector (2).
  10. Lay the harness aside.

    11. Object Number: 576198 Size: SH
  11. Remove the fuel rail attaching studs (2).
  12. Remove the fuel rail (1).
  13. Remove the injector lower O-ring seal from the spray tip end of each injector.
  14. Discard the O-ring seals.

Installation Procedure

    Notice: 

       • Use care when servicing the fuel system components, especially the fuel injector electrical connectors, the fuel injector tips, and the injector O-rings. Plug the inlet and the outlet ports of the fuel rail in order to prevent contamination.
       • Do not use compressed air to clean the fuel rail assembly as this may damage the fuel rail components.
       • Do not immerse the fuel rail assembly in a solvent bath in order to prevent damage to the fuel rail assembly.


    Object Number: 576198 Size: SH
  1. Lubricate the new lower injector O-ring seals with clean engine oil.
  2. Install the new O-ring seals on the spray tip end of each injector.
  3. Install the fuel rail (1).

    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 fuel rail attaching studs (2).

    5. Tighten
    Tighten the studs to 10 N·m (89 lb in).


    Object Number: 490817 Size: SH
  5. Connect the fuel injector electrical connectors (1) to each fuel injector (2).

    6. Object Number: 522654 Size: SH
  6. Install the fuel rail bracket retainer nut.

    7. Tighten
    Tighten the nut to 10 N·m (89 lb in).


    Object Number: 490597 Size: SH
  7. Install the PCV valve to the cam cover (2).
  8. Install the coolant surge tank inlet pipe (1). Refer to Surge Tank Pipe Replacement - Inlet in Engine Cooling.

    9. Object Number: 522644 Size: SH
  9. Install the PCV air tube to the cam cover.

    10. Object Number: 522641 Size: SH
  10. Connect the fuel pressure regulator vacuum hose.

    11. Object Number: 575657 Size: SH
  11. Connect the fuel feed and return pipes (2, 3) to the fuel rail. Refer to Metal Collar Quick Connect Fitting Service .
  12. Connect the negative battery cable. Refer to Battery Negative Cable Disconnection and Connection in Engine Electrical.
  13. Inspect for fuel leaks.
    14. 13.1. Turn ON the ignition for 2 seconds.
    13.2. Turn OFF the ignition for 10 seconds.
    13.3. Turn ON the ignition.
    13.4. Inspect for fuel leaks.
  14. Install the fuel injector sight shield. Refer to Fuel Injector Sight Shield Replacement in Engine Mechanical-4.0L.