Hesitation, Stumble on Acceleration (Recalibrate PCM)

Some owners may comment on an intermittent hesitation on acceleration during engine warm-up. No PCM diagnostic trouble codes will be stored, and no MIL will illuminate.

In some instances, the PCM fueling strategy may not be optimized during certain ambient temperatures.

1. Verify no PCM codes are stored. If PCM codes are stored, proceed with published diagnostic information found in the Service Information Manual. Once the conditions for the code have been corrected, proceed to step 2.
2. Recalibrate the PCM with the latest calibration. Calibrations are available from Techline starting September 2001, version 10.0.

The Calibrations are electronic calibrations and are NOT available from GMSPO. Calibrations are available from Techline starting September 2001, on the TIS 2000 version TIS 10.0/2001 data update or later.

For vehicles repaired under warranty, use: