GM Service Manual Online
For 1990-2009 cars only

A.I.R. SYSTEM NOISE AT IDLE NEW A.I.R. CHECK VALVE

CONDITION:

CHIRPING OR BUZZING NOISE FROM A.I.R. SYSTEM WHEN ENGINE IS IDLING, AND COMPUTER COMMAND CONTROL SYSTEM IS IN "OPEN LOOP" MODE. CAUSE: A.I.R. CHECK VALVE. CORRECTION: A NEW A.I.R. CHECK VALVE, PART NUMBER 22040200, IS BEING RELEASED FOR PRODUCTION, TO CORRECT THE ABOVE NOISE CONDITION. THIS NEW VALVE IS AVAILABLE FROM GM PARTS FOR SERVICE USE ON CUSTOMER VEHICLES.

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.