INCORRECT OIL PRESSURE GAGE READING AT IDLE

OIL PRESSURE GAUGE READS IN THE RED WARNING ZONE AT HOT IDLE

VEHICLES AFFECTED: 1986-87 "F" CAR WITH GAUGE OPTION (U21) -----------------

Condition: Some 1986-87 "F" cars may have oil pressure gauges that read in --------- the red warning zone when the vehicle is operated at a normal hot idle condition.

Cause: The red zone on the oil pressure gauge extends up to ----- approximately 10 PSI (70 kpa) while a normal oil pressure at hot idle could be as low as 6 PSI (41 kpa).

Correction: Check the engine oil pressure with an external gauge. If the ---------- measured pressure is greater than 6 PSI at idle and moves higher with increased engine speed, the oil pressure is normal. Replace the tach and oil pressure gauge assembly with one that has a reduced red warning zone. Use the following chart to determine the correct part numbers.

Part Number Country Engine ----------- ------- -------

25112206 Canada 5.OL (Codes H and F) 25112208 Canada 5.OL, 5.7L (Codes G and 8) 25112091 Canada 2.8L (Code S)

Use applicable labour time and number.

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.