Achieva V6-3100 3.1L MFI VIN M (1994)
Engine Control Module: Customer Interest
Engine - Tip-in Hesitation on Light Throttle Accel
File In Section: 6E - Engine Fuel & Emission
Bulletin No.: 67-65-30
Date: September, 1996
Subject:
Tip-in Hesitation on Light Throttle Acceleration (New Flash PROM)
Models:
1994-95 Buick Skylark
1994-95 Chevrolet Beretta, Corsica
1994-95 Oldsmobile Achieva
1994-95 Pontiac Grand Am
with 3100 V6 Engine (VIN M - RPO L82)
Condition
Some owners may experience a slight tip-in hesitation on light throttle acceleration during the engine's warm up cycle.
Cause
Due to engine system variation, it is possible to shift the vehicle "rich" if the vehicle has been updated with a flash prom from service bulletin
57-65-24A. The flash proms in that bulletin were to address vehicles that were "lean" and causing stalls. It is possible to shift a vehicle "rich" with those
calibrations and thus induce a rich hesitation. If that has occurred, new calibrations are available to "lean" the enrichment algorithm below coolant
temperatures of 8O°C (l76°F).
Correction
If service bulletin 57-65-24A has been performed and the vehicle exhibits a slight tip-in hesitation during warm up and normal diagnostics fail to show a
cause, then install a new flash prom.
Parts Information
The complete listing of new flash proms will be available for Techline Tools starting with CD # 14 release from the GM Service Technology Group
(STG).
Important:
Do not attempt to order the flash proms from GMSPO. The flash proms are programmed into the vehicle's Powertrain Control Module (PCM) via a
Techline Tool device.
^
Requires Service Bulletin 47-71-31 (Replacement of Final Drive Assembly to have been performed). The standard axle ratio is a 2.97.
Warranty Information
