GM Service Manual Online
For 1990-2009 cars only

CORRECT OIL PRESSURE READING DIAGNOSIS AND SWITCH P/N

Models ALL 6000, AND FIREBIRD MODELS EQUIPPED Affected:WITH 2.8L V-6 ENGINES (LB6/LB8)

Condition:

--------- Comments have been received on perceived 1OW oil pressure at idle with the above engine. The minimum oil pressure at hot idle with this engine should be 6 PSI (Pounds Per Square Inch).

The dash gage should never be used as a final reading on any engine. An external gage should always be used. This gage should have a full scale reading of no more than 60 PSI, and should be checked regularly for accuracy.

Correction:

---------- 1. On 6000 models with instrument clusters having both a gage and a warning light, the warning light may flicker at idle. If this condition is found, replace the sender with P/N 10068576.

2. On cars With standard warning lights, the light may flicker at idle. If the external gage check above indicates sufficient pressure at idle, replacement of the oil pressure Switch should correct the condition.

3. On cars With standard analog gages, the needle may just touch the red band of the gage at idle. If the external gage check above indicates sufficient pressure at idle, the customer should be informed that this condition is normal, as long as the pressure goes up immediately when engine RPM is increased. Several cars are being changed in production to decrease the width of the red band to proper limits.

It is acceptable for an engine that is hot to read as low as 6 PSI at idle. The oil reading should go up immediately when RPM is increased. Only when oil pressure is below 6 PSI at idle, or stays low at higher engine RPM, should engine repairs be attempted.


Object Number: 84468  Size: FS

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.