Tech Tip: Chevy Malibu Suffers Engine Hesitation, Stalling, RPM Drop – UnderhoodService

Tech Tip: Chevy Malibu Suffers Engine Hesitation, Stalling, RPM Drop

Some Malibu owners 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.

Models: 2004-’05 Chevrolet Malibu with 2.2L engine (VIN F — RPO L61), built prior to VIN breakpoint 5F132617

Condition
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.

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

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

Install a diode protected jumper harness (P/N 15242642) into the cooling fan circuit using the following instructions.
1. Unplug the right fan plug and open the clip holding conduit at the fan.

2. Remove the clip from the jumper harness.

3. Connect the jumper harness to the fan connection.

4. Connect the harness connector to the jumper harness.

5. Place the jumper in the existing clip and close the clip.

6. Without straining the wiring, gently gather the excess wiring harness and attach it to the fan motor support below the connector with an appropriate wire tie. Trim off any excess wire tie. The wiring should not be able to become entangled in the accessory drive.

Courtesy of Identifix.

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