LY6 Cold Start Idle Concern, Engine Sags While Shifting Into Drive or Reverse (Reprogram PCM)

Some customers may comment that the vehicle's engine sags while shifting into drive or reverse when it is cold outside.

The powertrain control module (PCM) calibration may allow the vehicle's engine idle to sag when the engine coolant temperatures are around 8°C (47°F) while shifting into drive or reverse.

Reprogram the PCM with the updated calibration.

Due to the length of this programming event, we strongly recommend the following precautions:

Notice: Before reprogramming, check the battery condition to prevent a reprogramming error of any of the modules due to battery discharge. Battery voltage must be between 12 and 16 volts during reprogramming. If the vehicle battery is not fully charged, use jumper cables from an additional battery. Be sure to turn off or disable any system that may put a load on the battery, such as automatic headlamps, daytime running lights, interior lights, heating, ventilation, and air conditioning (HVAC) system, radio, engine cooling fan, etc. A programming failure or control module damage may occur if battery voltage guidelines are not observed.

Important: The ignition switch must be in the proper position. The Tech 2® will prompt you to turn the ignition ON, with the engine OFF. DO NOT change the position of the ignition switch during the programming procedure unless instructed to do so.

Important: If you experience programming issues utilizing the Pass-Thru method, please reattempt using the remote method with the Tech 2® and a "CANDi" module. If you are still experiencing programming issues, please call the Techline Customer Support Center for assistance.

An updated PCM calibration is now available to address this concern. This calibration, or any that follow, is designed to address this concern. Reprogram the PCM with the software now available in TIS2WEB using the Service Programming System (SPS). Use data version 2.5 for 2007 or later, available on TIS2WEB (website version of TIS) February 18, 2007; and on TIS DVD version 3.0 / 2007 or later, mailed to dealers beginning March 14, 2007.

If you cannot access the calibration, call the Techline Customer Support Center at 1-800-828-6860 (English) or 1-800-503-3222 (French) and it will be provided. As always, make sure your Tech 2® Diagnostic Scan Tool is updated with the latest software version.

Important: DTCs may be set during programming and additional reprogramming time is required for downloading the operation files with the calibration files.

Clear any codes and verify the condition has been fixed.

For vehicles repaired under the 8 year/80,000 mile (130,000 kilometer) emission controller warranty, use: