GM Service Manual Online
For 1990-2009 cars only

ENGINE OVERHEATING POSSIBLE THERMOSTAT STICKING

VEHICLES AFFECTED: 1987 'N' SERIES WITH 2.5L ENGINE (VIN CODE U)

Some 1987 "N" models built between February 15, 1987 and May 18, 1987 with a 2.5L engine may have thermostats which are suspect for sticking. This could result in overheating or owner comment of an intermittent "TEMP" light.

If this condition is encountered, inspect the radiator and coolant hoses for adequate coolant flow as the engine reaches normal operating temperatures.

If coolant flow is reduced or condition is intermittent, replace the thermostat with part number 3059793.

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.