Beginning with the Start of 1990 Production for all models listed above, the vehicles were built with a fuel filter base that no longer contains a restriction switch (vacuum sensor). It can be seen that the restriction switch labeled as number 13 in Figure #2 has been deleted from the present configuration as shown in Figure #1. The model 80 fuel filter base has the same exterior form.
The Service Part number has not changed. Therefore, fuel filter bases ordered through CANSPO will not have a restriction switch. When installing a new fuel filter base on a 1989 or earlier model the restriction switch connector from the wiring harness will not be connected to the fuel filter base. The unused connector should be taped back to the wiring harness to prevent damage.
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.