GM Service Manual Online
For 1990-2009 cars only

Removal Procedure

Tools Required

Injection Pump Wrench

  1. Remove the negative battery cables. Refer to in General Information.
  2. Remove the intake manifold. Refer to Intake Manifold Removal.
  3. Remove the injection lines. Refer to
  4. Remove the fuel inlet line from the injection pump.
  5. Remove all necessary harness connectors and hoses from the injection pump.
  6. Remove the fuel return line at the top of the injection pump.
  7. Remove the oil fill tube.
  8. Remove the grommet for oil filler tube.

  9. Object Number: 27614  Size: SH
  10. Rotate the engine to gain access to the bolts (1) that hold the driven gear to the injection pump. Access is gained through the oil filler neck hole.
  11. Remove the driven gear bolts.
  12. Important : Never engage the starter motor to rotate the engine when the injection pump is removed as severe engine damage will occur. With the injection pump removed the pump driven gear could jam in the front housing by engaging the starter motor, resulting in a sheared crankshaft or camshaft gear key and possible valve train damage. Always bar the engine over by hand to avoid internal engine damage.


    Object Number: 193160  Size: SH
  13. Remove the injection pump flange nuts. Use the njection pump wrench.

  14. Object Number: 193162  Size: SH
  15. Remove the injection pump.
  16. Cap all open lines and nozzles.
  17. Remove the flange gasket.

Installation Procedure

  1. Install the new flange gasket on the injection pump .

  2. Object Number: 27612  Size: SH
  3. Adjust the locating stud (1) to the proper position to match with the slotted/elongated hole in the driven gear.
  4. Important: Be sure the locating stud (1) on the injection pump hub goes into the slotted/elongated hole in the driven gear.


    Object Number: 27613  Size: SH
  5. Install the injection pump making sure the locating stud is positioned within the slotted/elongated hole (3) in the driven gear.

  6. Object Number: 193160  Size: SH
  7. Install the injection pump flange nuts.
  8. Tighten
    Tighten nuts to 40 N·m (30 lb ft).


    Object Number: 27614  Size: SH

    Important: All the driven gear bolts should not be torqued until all the bolts are installed. This will allow for the proper alignment of all the bolt holes.

  9. Install the driven gear bolts (1).
  10. Tighten
    Tighten the bolts to 25 N·m (18 lb ft).

  11. Install the grommet for oil filler tube.
  12. Install the oil filler tube.
  13. Install the fuel feed line at the injection pump.
  14. Install the fuel return line to the top of the injection pump.
  15. Install all necessary harness and connectors.
  16. Install the injection lines. Refer to the tags on lines. Refer to
  17. Install the intake manifold. Refer to Intake Manifold Installation.
  18. Install the negative battery cables.
  19. Adjust the injection timing. Refer to