When a 1985 or 1986 model car listed above is operated at high ambient temperatures, with the air conditioning on, and under the operating conditions listed below; the driver may experience intermittent reduced air conditioning performance. - Driving up long, steep highway grades. - Idling the engine. - Driving in congested city traffic.
This reduced air conditioning performance may be the result of insufficient air flow through the condenser core. To improve this air flow, a new coolant fan air conditioning pressure switch, with lower turn on pressure, went into production effective with the following serial numbers:
1986 LeSabre GH405213 1986 Electra GH429394
1986 Delta 88 Wentzville 1 Start of Production Willow Run W GW307568
1986 Ninety-Eight Lake Orion 4 G4317393 Wentzville 1 G1312436
To repair this condition on vehicles built before the breakpoints listed, replace the coolant fan air conditioning pressure switch with part number 25527510.
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.