Engine - Cold Start Stall and/or Chuggle

91buick07

Bulletin: 91-6E-21

Date: August 91

Ref. No.: 91-200-6E

Corp. Ref. No.: 106503R


SUBJECT: COLD START STALL AND/OR CHUGGLE AT 35-45 MPH WITH TORQUE CONVERTER CLUTCH ENGAGED (REVISED CALIBRATION MEM-CAL)

MODELS AFFECTED: 1989-91 PARK AVENUE/ULTRA AND LESABRE MODELS WITH 3800 (CODE C) ENGINES ONLY


Some owners of 1989 through 1990 Park Avenue/Ultra and 1989-1991 LeSabre models equipped with the 3800 (Code C) engine may experience one or both of the following conditions:

^ Engine does not stay running on initial cold start.

^ Chuggle at 35-45 mph with torque converter clutch engaged.

The two conditions are independent of each other, yet it may be possible for both conditions to exist on one vehicle.

Follow the information outlined under the individual heading for that condition:

ENGINE DOES NOT STAY RUNNING ON INITIAL COLD START

If the vehicle's basic engine controls and fuel systems are operating properly, it is important for the technician to be familiarized with information contained in Service Bulletin 91-6E-3, "Recommended fuels for non-turbo port fuel injection engines". If the condition cannot be repaired by changing fuel or using currently published service and diagnostic procedures, it may be necessary to install a revised calibration MEM-CAL. Install MEM-CALS listed in Table A for this condition only.

Figure 1:

CHUGGLE AT 35-45 MPH WITH TORQUE CONVERTER CLUTCH ENGAGED

Proceed with the diagnostic flow chart (Figure 1) to aid in identifying the possible cause of the condition.

Note: The new revised calibration MEM-CALS may affect fuel economy. Be sure to advise the vehicle owner of this fact.


ENGINE DOES NOT STAY RUNNING ON INITIAL COLD START AND
CHUGGLE AT 35-45 MPH AND WITH TORQUE CONVERTER CLUTCH ENGAGED

Should owners' comments indicate both conditions exist. Follow steps outlined in both procedures. The two conditions are independent of each other. If it is determined that a new revised calibration MEM-CAL is necessary to correct both conditions, select MEM-CALS listed in Table B.

Note: The new revised calibration MEM-CALS in Table B may affect fuel economy. Be sure to advise the vehicle owner of this fact.

TABLE "A"

SCANNER ID WITH BROADCAST SERVICE
YEAR MODEL AXLE RATIO MEM-CAL INSTALLED CODE PART #

1989-90 Park Avenue/ 2.84 5614 AYLA 16165848
Ultra NATL/CALIF
1989-91 LeSabre

1989-90 Park Avenue/ 2.97 5634 AYLC 16165839
Ultra NATL/CALIF
1989-91 LeSabre
TABLE "B"

SCANNER ID WITH BROADCAST SERVICE
YEAR MODEL AXLE RATIO MEM-CAL INSTALLED CODE PART #

1989-90 Park Avenue/ 2.84 5624 AYLB 16165843
Ultra NATL/CALIF
1989-91 LeSabre

1989-90 Park Avenue/ 2.97 5644 AYLD 16165829
Ultra NATL/CALIF
1989-91 LeSabre

Parts are currently available from GMSPO.

WARRANTY INFORMATION:

Labor Operations No.: T0500
Labor Time: .7 Hr. (Replace MEM-CAL)
.2 Hr. (Add to complete chuggle
Diagnostic Flow Chart Only)