A/C Compressor - Operation During Start-Up

91buick01

Bulletin 91-6E-8


Date Feb. '91


Ref. No. 91-083-6E


Corp. Ref. No. 006505


SUBJECT: A/C COMPRESSOR OPERATION DURING START-UP TO CONTROL RPM FLARE VEHICLES EQUIPPED WITH THE 3800 T.P.I. ENGINE (VIN L)


MODELS AFFECTED: 1991 PARK AVENUE ULTRA WITH 3800 T.P.I. ENGINE (VIN L) BUILT PRIOR TO M1626149, 1990-91 REGAL MODELS, FEDERAL EMISSIONS - BUILT PRIOR TO M1813629, 1990-91 REGAL MODELS, CALIFORNIA EMISSIONS, BUILT PRIOR TO M1813961


From start of production, the above vehicles with listed serial numbers, allows during each ignition cycle the A/C compressor to engage, up to five seconds, to minimize engine RPM flare with the A/C mode switch in the on or off position. A/C compressor engagement during start-up on vehicles that have a sudden loss of refrigerant or have lost all the refrigerant over a period of time, may contribute to an A/C compressor failure.


If a technician is servicing the A/C system on a vehicle built prior to the breakpoint listed, it is recommended that a new calibration mem-cal be installed, in conjunction with the A/C system repairs.


The new calibration will eliminate A/C compressor operation during engine start-up.


The mem-cals are currently available through GMSPO under the following part numbers.

SCANNER
ID IF
APPLI- AXLE MEM-CAL BROAD- SERVICE
YEAR MODEL CATION RATIO INSTALLED CAST PART #

1991 Park Ave./Ultra Fed. F17/2.84 9994 AXDH 16160178
1991 Park Ave./Ultra Calif. F17/2.84 0004 AXDJ 16160173
1991 Park Ave./Ultra Fed. opt. 3.06 * 0014 AXDK 16160168
1991 Park Ave./Ultra Calif. opt. 3.06 * 0024 AXDL 16160163
1990-91 Regal Fed. All 0044 AXDN 16160153
1990-91 Regal Calif. All 0054 AXDP 16160148

* Part of Option Package Y56 or V92


IMPORTANT: The new calibration mem-cals are currently being used in production. Verify if this mem-cal is already installed by the scanner I.D.


WARRANTY INFORMATION:


Use applicable Labor Time Guide Operation Number and Time.