WHISTLE NOISE FROM RIGHT COWL VENT AREA (RPL. VENT ACTUATOR)

SUBJECT: WHISTLE NOISE FROM RIGHT COWL VENT AREA (REPLACE VENT ACTUATOR)

VEHICLES AFFECTED: 1992-93 "S/T" TRUCKS WITH AIR CONDITIONING

CONDITION:

Some owners of 1992 and 1993 "S/T" Trucks equipped with air conditioning may experience a whistling noise from the right cowl vent area when the air conditioning controls are in the BI-LEVEL mode or when switching from the MAX to NORMAL models.

CAUSE:

The whistle noise is caused by air being forced past the vent seal.

CORRECTION:

To correct this condition a revised vent door actuator with a stronger spring applying additional force to the vent door has been released. the revised actuator was released in production beginning with the following VINS:

MORAINE GMC 1GKDT13W4P2515620 CHEVROLET 1GNDT13WXP2140318 OLDSMOBILE 1GHDT13W9P2703913

PONTIAC WEST GMC 1GTCS19Z4PO510568 CHEVROLET 1GCCS14A4PO131510

SHREVEPORT GMC 1GTCS14ROP8510883 CHEVROLET 1GCCS14R6P8143456

SERVICE PROCEDURE:

Follow "Plenum Side Vent Actuator Replacement" procedure outlined in section 1B of the 1993 "S/T" Service Manual.

SERVICE PARTS INFORMATION:

PART NUMBER DESCRIPTION QTY.

1996833 Actuator, Inside Air Valve 1

For vehicles repaired under warranty use:

Labour Operation: D1790 Actuator Vacuum Diaphragm, Replace Labour Time: .5 Hours

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.