GM Service Manual Online
For 1990-2009 cars only
Makes 🢒 GMC_Truck 🢒 2009 🢒 Sierra - 4WD 🢒 Diagnostic Navigation 🢒 Vehicle Diagnostic Information 🢒 Spark Plug Wire Replacement

Removal Procedure

    Object Number: 1876875 Size: SH

    Note: Prior to removing the spark plug wire(s) note the correct routing of the wires as required.

  1. Remove the appropriate spark plug wire boot(s) (1, 2) from the ignition coil.
    2. 1.1. Twist the spark plug boot 1/2 turn.
    1.2. Pull ONLY on the spark plug boot or use a tool designed for this purpose, in order to remove the spark plug wire boot from the ignition coil.

    Object Number: 1876924 Size: SH
  2. Remove the appropriate spark plug wire boot(s) (2) from the spark plug. (left side shown, right similar).
    3. 2.1. Twist the spark plug boot 1/2 turn.
    2.2. Pull ONLY on the spark plug boot or use a tool designed for this purpose in order to remove the spark plug wire boot from the spark plug.
  3. Open the spark plug wire separators (1).
  4. Remove the appropriate spark plug wire(s).

Installation Procedure

    Object Number: 1876924 Size: SH

    Caution: If the boot to wire movement has occurred, the boot will give a false visual impression of being fully seated. Ensure that the boots have been properly assembled by pushing sideways on the installed boots. Failure to properly seat the terminal onto the spark plug will lead to wire core erosion and result in an engine misfire or crossfire condition, and possible internal damage to the engine.

  1. If reinstalling the old spark plug wires, apply dielectric grease GM PN  12345579 (Canadian PN 10953481), or equivalent to the inside the spark plug wire boots.
  2. Install the appropriate spark plug wire(s)
  3. Close the spark plug wire separators (1).
  4. Install the appropriate spark plug wire boot(s) (2) to the spark plug. (left side shown, right similar).

    5. Object Number: 1876875 Size: SH
  5. Install the appropriate spark plug wire boot(s) (1, 2) to the ignition coil.

    6. Object Number: 1876925 Size: SH
  6. Inspect the spark plug wires for proper routing (1, 2, 3, 4, 5, 6) and installation.
    7. 6.1. Push sideways on each boot in order to inspect the seating.
    6.2. Reinstall any loose boot.
    6.3. Any time the spark plug wire or boot are installed on the spark plug, new dielectric grease needs to be applied inside the boot.