PROM - Intermittent Hesitation or Lack of Power on Accel
File In Section: 06 - Engine/propulsion SystemBulletin No.: 99-06-04-050
Date: October, 1999
Subject:
TECHNICAL
Intermittent Hesitation or Lack of Power On Acceleration (Reprogram PCM)
Models:
1999 Oldsmobile Alero
1999 Pontiac Grand Am with 3.4 L Engine (VIN E - RPO LA1)
Condition
Some owners may comment about an intermittent hesitation or lack of power on acceleration. The malfunction indicator lamp (MIL) will not be illuminated, and no codes will be stored. If ESC spark advance is monitored with a TECH II scan tool during the condition, a reduction in ESC spark advance (typically 14-19 degrees) will be observed.
Cause
Condition may be caused by the knock sensor interpreting normal engine harmonics as combustion detonation.
Correction
A revised calibration has been released to correct this concern. Reprogram the PCM using the correct calibration listed below.
Parts Information
The calibrations listed are electronic calibrations and are NOT available from GMSPO. Calibrations will be available from Techline starting August 1999, on the TIS 2000 Disc 16 CD ROM or Techline Disc 16/17 CD ROM.
Warranty Information
For vehicles repaired under warranty, use:
Labor
Operation Description Labor Time
J6355 On Car Reprogramming Use published
labor operation
time