AIR CLEANER BRACKET NOISE-BUZZ VIBRATION (INSTALL NEW ASSY.)

Subject: BUZZ OR VIBRATION COMING FROM BEHIND INSTRUMENT PANEL

Model and Year: 1992 CAPRICE WITH 4.3L (LB4 - VIN Z) V6 ENGINE

CONDITION:

--------- Some owners of 1992 B Cars (Chevrolet Caprice) equipped with 4.3L (LB4, VIN Z) V6 engines may report a buzz or vibration that seems to be originating behind the instrument panel.

CAUSE:

----- 1992 model year production air cleaner bracket. The 1992 production air cleaner bracket has three legs. Two of the legs are bolted to the inlet manifold. The third unattached leg could possibly vibrate, causing the reported buzz or vibration noise.

CORRECTION:

---------- Install the 1993 model year production air cleaner bracket assembly (P/N 10241668). All three legs of the 1993 model year bracket assembly are bolted to the inlet manifold.

IMPORTANT: The vehicle should NEVER be returned to the customer for use without the AIR CLEANER BRACKET ASSEMBLY installed. The air cleaner bracket is necessary to maintain the integrity of the fuel system during a severe frontal collision.

SERVICE PROCEDURE:

DISASSEMBLY

1. Remove air cleaner assembly.

2. Remove air cleaner bracket assembly.

3. Loosen the right bolt of the exhaust gas recirculation (EGR) valve. Back the bolt out just far enough to install the new air cleaner bracket assembly.

INSTALLATION

1. Position the new air cleaner bracket assembly.

2. Hand start the two nuts for the air cleaner bracket assembly.

3. Torque air cleaner bracket assembly nuts to 25 N.m (18 lb-ft).

4. Torque the right bolt of the EGR valve to 20 N.m (15 lb-ft).

5. Install air cleaner assembly.

SERVICE PARTS INFORMATION:

PART NO. DESCRIPTION QTY. -------- ----------- ---- 10241668 Air Cleaner Bracket Assembly 1

Parts are expected to be available on May 24, 1993.

WARRANTY INFORMATION:

Labor Operation: T3335 (R&R Air Cleaner Bracket Assembly) Labor Time: 0.4 Hour

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.