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Headlamps and/or Interior Lamps Flicker (Replace Ignition Coil and Add Ground Strap)

Subject:Headlamps and/or Interior Lamps Flicker (Replace Ignition Coil and Add Ground Strap)

Models:2007 Chevrolet Impala, Monte Carlo
with 3.9L Engine (VIN Code R -- RPO LZ8)



Condition

Some customers may comment that the headlamps and/or interior lamps flicker while driving.

Upon investigation, the technician may find that the lamps flicker when switching between 3 and 6 cylinder mode, mostly at highway speeds.

Correction

Replace the ignition coil and add ground strap following the procedure below.

  1. Remove the intake manifold cover.
  2. Disconnect the ignition coil electrical connector.
  3. Disconnect the left side spark plug wires from the ignition coil.
  4. Disconnect the right side spark plug wires from the ignition coil.
  5. Remove the 4 bolts attaching the ignition coil to its mounting bracket and remove the ignition coil.
  6. Remove the ignition coil from the mounting bracket.
  7. Loosen the 2 lower ignition coil mounting bracket nuts.
  8. Remove the 2 upper ignition coil mounting bracket bolts and discard.

  9. Object Number: 1958219  Size: SH
  10. Install the ground strap (1), P/N 12581176, to the upper left side of the bracket as shown between the coil bracket and intake. Install the new bracket bolt, P/N 11515756, (do not tighten at this time). Prior to installing the ground strap, remove the captured nut and washers. they are not needed (simply pound them out with a hammer on a vise).
  11. Install the washer (2), P/N 02436162, to the upper right side of the bracket between the coil bracket and intake. Install the new bracket bolt, P/N 11515756, (do not tighten at this time).
  12. Tighten
    Tighten all the ignition coil bracket bolts and nuts to 25 N·m (15 lb ft).

  13. Install the new ignition coil to the mounting bracket.

  14. Object Number: 1958221  Size: SH
  15. Install the other end of the ground strap to the coil as shown and secure using a new bolt, P/N 11588715.
  16. Install the other 3 ignition coil bolts.
  17. Tighten
    Tighten the bolts to 10 N·m (89 lb in).

  18. Connect the right side spark plug wires to the ignition coil.
  19. Connect the left side spark plug wires to the ignition coil.
  20. Connect the ignition coil electrical connector.
  21. Install the intake manifold cover.

Parts Information

Part Number

Description

Qty

12595088

Coil Assembly, Ignition

1

12581176

Ground Strap

1

11588715

Bolt

1

02436162

Washer

1

11515756

Bolt

2

Warranty Information

For vehicles repaired under warranty, use:

Labor Operation

Description

Labor Time

J7717*

Replace Ignition Coil and Add Ground Strap

0.5 hr

*This is a unique labor operation number for bulletin use only. This number will not be published in the Labor TIme Guide.