PERIODIC VACUUM GEN. EXHAUST (CONDITION & EXPLANATION)

A VACUUM GENERATOR (WHICH PROVIDES VACUUM FOR A/C CONTROLS) IS OPERATED BY VEHICLE AIR SYSTEM PRESSURE AND IS MOUNTED ON THE AIR CONDITIONING EVAPORATOR BLOWER ASSEMBLY. UNDER NORMAL CONDITIONS WITH THE ENGINE OFF, THE VACUUM GENERATOR MAY PERIODICALLY EXHAUST A SMALL AMOUNT OF AIR. THIS WILL CONTINUE UNTIL THE AIR CIRCUIT IS DEPLETED. PERIODIC EXHAUSTING OF THE VACUUM GENERATOR IS NORMAL AND IT SHOULD NOT BE CHANGED FOR THAT REASON. ADDITIONAL INFORMATION ON THIS ITEM CAN BE FOUND IN THE MAINTENANCE MANUAL, GROUP 1B.

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.