Some customers driving 1987-88 Chevrolet or Pontiac "J" or "L" models equipped with a 2.8L engine (VIN Code W) may comment on the following:
1). Low coolant light flashing during acceleration.
2). Temperature gage needle pointing toward hot range.
3). Coolant not flowing from the reservior bottle to the radi.ator.
These comments may be the result of air trapped in the coolant system preventing proper system fill and/or a damaged seal surface for the coolant filler cap assembly.
If customer comments relative to a coolant system concern are received, then please complete the following service procedure.
1). Review service procedure as detailed in Section 6B of the service manual.
2). Inspect the coolant filler assembly for damage to the filler cap sealing surfaces.
3). Verify filler cap function by removing the coolant recovery hose at the filler assembly and applying a vacuum to the recovery hose fitting.
4). Repair or replace the coolant filler assembly or filler cap assembly as required.
5). Fill and pressure check the coolant system. Check the coolant recovery hose and connections for coolant leaks. Repair as required.
6). Verify that the cooling system is full by test driving the vehicle until the engine has reached normal operating temperatures.
Use applicable Labour Time and Operation 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.