For 1990-2009 cars

# A/C SYSTEM EVACUATION PROCEDURE REVISION

THE EVACUATING PORTION OF THE DISCHARGING, ADDING OIL, EVACUATING AND CHARGING PROCEDURE FOR C.C.O.T. AIR CONDITIONING SYSTEMS HAS BEEN REVISED FOR ALL 1981 MODEL CARS.

THE NEW, MORE EFFICIENT PROCEDURE ALLOWS THE A/C SYSTEM TO BE EVACUATED ONLY UNTIL THE VACUUM GAGE REACHES 28 OR 29 INCHES OF MERCURY (VACUUM), OR ITS EQUIVALENT AS ADJUSTED FOR ALTITUDE. THIS CHANGE ELIMINATES THE ADDITIONAL 15 MINUTE EVACUATION TIME PREVIOUSLY REQUIRED AFTER REACHING THE SPECIFIED MERCURY (VACUUM) LEVEL.

THE NEW PROCEDURE WILL APPEAR IN ALL FUTURE SERVICE MANUAL PUBLICATIONS AND THE 1981 LABOR TIME GUIDE WILL BE PUBLISHED WITH A REVISED TIME OF .5 HOURS WHICH REFLECTS THIS PROCEDURE CHANGE.

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.