Some 1985 FWD-C vehicles, between B.C. No. 224776 through 226375, may experience an excessive vacuum pump noise or vibration due to a revised vacuum pump mounting bracket.
A support brace, added to the mounting bracket on vehicles within the above VIN range, may transmit a higher vacuum pump noise than the previous design. This support brace may be removed from the bracket to reduce vacuum pump noise. The support brace should be removed from the bracket as follows:
1. Raise vehicle on hoist.
2. Remove electrical connector and two vacuum hoses from vacuum pump.
3. Remove three 13mm screws securing vacuum pump mounting bracket to frame and remove pump and bracket assembly.
4. Using a hacksaw, cut the brace in the areas shown in Figure 1.
5. Reinstall bracket, electrical connector and two vacuum hoses.
6. Lower vehicle.
For warranty purposes, use labor Operation No. T6103 at .3 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.