Severe Hesitation, Drop of Engine RPM or Idle Stall (Install Jumper Harness)

This bulletin is being revised to add the 2005 Model Year. Please discard Corporate Bulletin Number 04-06-03-010 (Section 06 -- Engine).

Some customers may comment on the engine having a severe hesitation or a drop in RPM during parking lot maneuvers or during a deceleration. In a few instances, customers may comment on occasionally experiencing a stall at idle when the engine is fully warmed.

The engine cooling fan may be inducing a voltage spike that effects the ignition system.

Replacement of the crankshaft position sensor has not been shown to be an effective repair for this condition.

Install a diode protected jumper harness into the cooling fan circuit using the following instructions.

1. Unplug right fan plug and open clip holding conduit at fan.
2. Remove clip from jumper harness.
3. Connect jumper harness to fan connection.
4. Connect harness connector to jumper harness.
5. Place jumper in existing clip and close clip.
6. Without straining the wiring, gently gather excess wiring harness and attach to the fan motor support below the connector with an appropriate wire tie. Trim off any excess wire tie. Wiring should not be able to become entangled in the accessory drive.

Parts are currently available from GMSPO.

For vehicles repaired under warranty, use: