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For 1990-2009 cars

ENGINE BUZZ OR WHINE LOOSE ENGINE MOUNTING BOLT

ENGINE BUZZ OR WHINE DUE TO LOOSE ENGINE MOUNTING BOLT (Illustration has been revised and Service Note added.)

VEHICLES AFFECTED: 1987 N CAR WITH 3.0L (VIN CODE L) ------------------

A whine, buzz or missing bolt on a 1987 N Car with a 3.0L VIN Code L engine with A/C may be caused by an engine mounting bracket bolt losing sufficient torque.

Inspect the right front engine mounting bracket for a loose or missing bolt, see Fig. 1. Follow the steps outlined below for repair:

Step 1. If bolt is missing, replace it with part number 11509793 and torque to 60-80 N.m (44-60 lbs. ft.).

Step 2. If bolt is loose, remove the bolt, clean the threads and apply Loctite 242 or equivalent to the bolt threads. Torque bolt to 40-60 N.m (30-44 lbs. ft.).

The new bolt (Part No. #11509793) was in production 4-13-87, breakpoints:

Oldsmobile HM278190 Buick HM065673 Pontiac HC870266

SERVICE NOTE: Locating bolt shown in Figure 1 must be removed after all engine mounts are secured or engine vibration and noise will be transmitted into car body.


Object Number: 88169  Size: LF

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.