GM Service Manual Online
For 1990-2009 cars only

Glow Plug Replacement Without CTF

Inspection Procedure

The glow plugs can be tested in 2 ways:

   • 
Object Number: 736696  Size: SH
  • Take an amperage draw test with an inductive pick-up lead at each glow plug. The rated amp draw should be 3.0-4.5 amps per glow plug. Or install the inductive current clamp around the glow plug power supply wire. Take the systems current draw reading and divide the reading by the number of glow plugs in the system.
  •    • 
    Object Number: 736699  Size: SH
  • A continuity test can also be made with an ohmmeter between the glow plug lead and ground, with the buss bars removed. If no continuity exists, the glow plug will not heat and should be replaced.
  • Removal Procedure

    1. Remove the air cleaner layer. Refer to Air Cleaner Replacement .
    2. If required, remove the engine cover. Refer to Engine Cover Replacement .

    3. Object Number: 736691  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.

    4. Disconnect the negative battery cables.
    5. Disconnect the glow plug power supply wire.
    6. Disconnect the glow plug buss bar.
    7. If removing the #6 glow plug, remove the #6 injector pipe. Refer to Fuel Injector Replacement .
    8. Remove the glow plugs from the cylinder head.

    Installation Procedure

      Notice: Refer to Component Fastener Tightening Notice in the Preface section.


      Object Number: 736691  Size: SH
    1. Install the glow plugs to the cylinder head.
    2. Tighten
      Tighten the glow plugs to 20 N·m (15 lb ft).

    3. If required, install the #6 injector pipe to the #6 injector. Refer to Fuel Injector Replacement .
    4. Install the glow plug buss bar.
    5. Tighten
      Tighten the glow plug buss bar to 1.2 N·m (11 lb in).

    6. Connect the glow plug power supply wire.
    7. Connect the negative battery cables.
    8. If required, install the engine cover. Refer to Engine Cover Replacement .
    9. Install the air cleaner layer. Refer to Air Cleaner Replacement .

    Glow Plug Replacement With CTF

    Inspection Procedure

    The glow plugs can be tested in 2 ways:

       • 
  • Perform an amperage draw test with an inductive pickup lead at each glow plug. The rated amp draw should be 6.0-7.5 amps per glow plug. Or install the inductive current clamp around the glow plug power supply wire. Take the system's current draw reading and divide the reading by the number of glow plugs in the system.
  •    • 
    Object Number: 736696  Size: SH
  • A continuity test can also be made with an ohmmeter between the glow plug lead and ground with the buss bars removed. If no continuity exists, the glow plug will not heat and should be replaced.
  • Removal Procedure

    1. If required, remove the engine cover. Refer to Engine Cover Replacement .
    2. If required, remove the air cleaner layer. Refer to Air Cleaner Replacement .
    3. Disconnect the negative battery cables. Refer to Battery Negative Cable Disconnection and Connection .

    4. Object Number: 736696  Size: SH
    5. Disconnect the glow plug power supply wire.
    6. Disconnect the glow plug buss bar.
    7. Remove the glow plugs from the cylinder head.

    Installation Procedure

      Notice: Refer to Fastener Notice in the Preface section.

    1. Install the glow plugs to the cylinder head.
    2. Tighten
      Tighten the glow plugs to 20 N·m (15 lb ft).

    3. Install the glow plug buss bar.

      Tighten
      Tighten the glow plug buss bar to 1.2 N·m (10 lb in).


      Object Number: 736696  Size: SH
    4. Connect the glow plug power supply wire.
    5. Connect the negative battery cables. Refer to Battery Negative Cable Disconnection and Connection .
    6. If required, install the air cleaner layer. Refer to Air Cleaner Replacement .
    7. If required, install the engine cover. Refer to Engine Cover Replacement .