GM Service Manual Online
For 1990-2009 cars only

INTERMITTENT OIL LIGHT,PRESS. REG. PLUG, COLLAPSED LIFTERS

VEHICLES AFFECTED: 1984-85 Models with 3.0L & 3.8L V-6 Engines

Some vehicles may experience an intermittent oil light, usually when engine is first started, or a collapsed lifter condition where the cause was not determined.

These conditions may result from intermittent low oil pressure which may be due to the oil pump pressure regulator plug sticking in the bore.

If this condition is encountered, inspect the pressure regulator plug for free movement the full bore travel. Assure valve freeness and clean as necessary.

On 1984-85 3.8L engine and 1984 3.0L engine, the plug is a relief valve located in the oil pump cover.

On 1985 3.0L (VIN Code L) engines the pressure regulator plug is located in the front cover behind the oil filter adapter.

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.