OCCASIONAL ENGINE STALLING DIAGNOSTIC/NEW SERVICE MEMCAL

SUBJECT: OCCASIONAL ENGINE STALL (DIAGNOSTIC CHECKS AND NEW SERVICE MEMCAL) (Revised to update vehicles Affected)

VEHICLES AFFECTED: 1988 "A"(AWD) WITH/3.1, 1988 "J" WITH/ 2.8, 1989 "A/J/L/W" WITH 2/2.8L

THIS BULLETIN REPLACES PRODUCT SERVICE BULLETIN 89-628-109 TO UPDATE THE PART NUMBER FOR THE 1988 A PONTIAC "STE"MODEL.

Some customers driving the following cars;

- 1988 J-car with a 2.8L engine (VIN Code W) - 1989 A/J/L/W models with a 2.8L engine (VIN Code W) - 1988 "All All-Wheel-Drive model with a 3.1L engine (VIN Code T)

may comment concerning any of the following:

A cold start stall, A tip-in hesitation, or A decel stall

If a customer comment concerning an occasional engine stall or a drive hesitation is received, then complete the following:

1. Perform diagnostic checks, per Section 6E of the Service Manual and replace any defective components.

Proceed to Step #2 only if diagnostic checks uncover no cause for the customer comments.

2. Install a new MEMCAL, which may be obtained from CANSPO (reference the attached service part number chart).

IMPORTANT: The following procedure must be completed when removing and installing a 60 degree V6 Engine Control Module (ECM) MEMCAL (Reference Product Service Bulletin #89-628-102 dated 12/15/88.

a). Disconnect the battery.

b). Remove current MEMCAL and install a new service MEMCAL.

c). Restore the battery power and place air conditioning controls (if equipped) in the "off" position.

d). Firmly apply the parking brake and block the drive wheels. Start the engine, and shift the transaxle to "drive" for automatics or "neutral" for manuals.

e). Allow the engine to run until the engine cooling fan has cycled once, or a maximum of 10 minutes.

f). Turn the ignition key to the "off" position for at least 5 seconds.

g). Start the engine, and shift the transaxle to "drive" for automatics or "neutral" for manuals.

h). Allow engine to run for at least 5 minutes.

MEMCAL CHART

EMISSION SCANNER SERVICE YEAR DIVISION MODEL SYSTEM TRANS I.D. MEMCAL P/N ---- -------- ----- -------- ----- ------- ---------- 1989 W FED 5spd M/T MG2 7461 16147315 1989 W FED 4spd A/T ME9 8151 16138169 1989 J FED 5spd.M/T MG2 7421 16147309 1989 J FED 3spd A/T MD9 8121 16138219 1989 L FED 5spd M/T MG2 7441 16147312 1989 L FED 3spd A/T MD9 8101 16138210 1988 J FED 5spd M/T MG2 8261 16148227 1988 J FED 3spd A/T MD9 4761 16134468 1989 A FED 3spd A/T MD9 8021 16138174

Remarks: Except Oldsmobile and Buick "All cars with the type "QMB" (P215/6OR14)

1989 A FED 4spd A/T ME9 8041 16138184 1989 A FED 3spd A/T MD9 8061 16138193

Remarks: Oldsmobile and Buick A Cars With Tire Types "QMB" (P215/6OR14)

1988 A FED 3spd A/T MD9 2401 16150336

Remarks: Pontiac A Car STE Model (Special Touring Edition) Y88 (LHO 3.1L Engine) **

Parts are currently available from CANSPO.

** Codes may be found on Service Parts Identification Label.

General Motors bulletins are intended for use by professional technicians, not a "do-it-yourselfer". They are written to inform those technicians of conditions that may occur on some vehicles, or to provide information that could assist in the proper service of a vehicle. Properly trained technicians have the equipment, tools, safety instructions and know-how to do a job properly and safely. If a condition is described, do not assume that the bulletin applies to your vehicle, or that your vehicle will have that condition. See a General Motors dealer servicing your brand of General Motors vehicle for information on whether your vehicle may benefit from the information.