Engine Controls - Gauges Drop to Zero/Stalling Condition
Bulletin No.: 05-06-04-037Date: May 26, 2005
TECHNICAL
Subject:
Certain Instrument Panel Gauges Go To Zero and/or Intermittent Engine Stall (Repair Ground Connections and/or Reprogram Powertrain Control Module (PCM))
Models:
2005 Buick Allure (Canada), LaCrosse
2004-2005 Pontiac Grand Prix
with 3.8L V6 Engine (VIN 2 - RPO L26)
Condition
Some owners may comment that the fuel and the temperature gauge in the instrument panel intermittently go to zero while the speedometer and tachometer continue to operate normally. In addition, some may comment that the low fuel indicator is displayed in the Driver Information Center (DIC) when this occurs. In a small portion of these cases, the gauges going to zero may be followed by an engine hesitation or stall.
Cause
Intermittent high resistance or connection of the negative battery cable to the top of the right side frame rail may cause the I/P gauges to intermittently go to zero.
The intermittent stall condition may be caused by the following:
^ An internal calculation in the Powertrain Control Module (PCM) when determining barometric values under certain engine loads. When this occurs, the engine can take several minutes to restart.
^ Intermittent high resistance or connection of the negative battery cable to the top of the right side frame rail.
Correction
I/P Gauges Intermittently Go To Zero Condition
1. Remove the bolt (1) attaching the negative battery cable to the top of the frame rail.
2. Remove any corrosion from the cable end, the bolt and the top of the frame rail where the attachment is made.
3. Apply dielectric grease, P/N 12377900 (in Canada, P/N 10953529), to the cable end and frame rail.
Important:
The bolt being tightened in the next step MUST be tightened to the torque specification listed.
4. Position the ground cable to the frame rail and install the bolt. Refer to the illustration above.
Tighten
Tighten the bolt to 10-12 N.m (89-106 lb in).
Intermittent Engine Stall Condition
1. Remove the bolt (1) attaching the negative battery cable to the top of the frame rail.
2. Remove any corrosion from the cable end, the bolt and the top of the frame rail where the attachment is made.
3. Apply dielectric grease, P/N 12377900 (in Canada, P/N 10953529), to the cable end and frame rail.
Important:
The bolt being tightened in the next step MUST be tightened to the torque specification listed.
4. Position the ground cable to the frame rail and install the bolt. Refer to the illustration above.
Tighten
Tighten the bolt to 10-12 N.m (89-106 lb in).
Important:
For the 2004 Pontiac Grand Prix, there are two new calibrations available. The calibrations are based on the type of fuel tank installed in the vehicle. Vehicles that have had Corporate Service Bulletin Number 04-06-04-066 performed require a calibration for a "baffled" fuel tank. In addition, some late production 2004 models may have been built with the "baffled" tank. All others should have a "non-baffled" tank.
5. Update the PCM with a new calibration.
This calibration update corrects the barometric value to prevent intermittent engine hesitation, which may lead to engine stall. The calibration update affects 2004-2005 model year Pontiac Grand Prix vehicles with the L26 engine and 2005 model year Buick Allure/LaCrosse vehicles with the L26 engine. This calibration will be available to dealerships as part of TIS+2000 incremental satellite update 6.0 (NAO version 25.003). As always, make sure your Tech 2(R) is updated with the latest software version.
��7:
To determine which calibration is correct for the 2004 Pontiac Grand Prix, obtain the part number of the calibration currently in the PCM using a Tech 2(R). Compare that part number to that shown and reprogram the PCM with the corresponding new calibration. For the 2005 Pontiac Grand Prix and Allure/LaCrosse, the emission system determines the correct calibration.
Parts Information
Parts are currently available from GMSPO.
Warranty Information
For vehicles repaired under warranty, use the table.
Disclaimer