PORT FUEL INJECTOR CLEANING ON VEHICLE PROCEDURE
VEHICLES AFFECTED: All 1985 Port Fuel Injected Engines 1.8L, (VIN Code J), 2.8L, (VIN Codes S, W or 9), 3.0L, (VIN Code L), 3.8L, (VIN Codes B, 3, 7 or 9) 5.0L, (VIN Code F), 5.7L, (VIN Code 8) --------------------------------------------------
Various types of injector cleaning equipment are available to clean injectors on the vehicle. When injectors have been identified as being lean, they may be cleaned using available cleaning equipment and the proper chemical cleaner. Kent Moore is presently developing on vehicle cleaning equipment that should be available by October, 1985.
To clean lean injectors effectively, use a solution of 95% gasoline and 5% GM Top Engine Cleaner, P/N 992872, or AC-Delco Carburetor Tune-Up Conditioner, (X66-P). Use approximately 1.475L (50 ounces) of the solution. (1.4L (3 pints) of gasoline and 75ml (2.5 ounces) of GM Top Engine Cleaner or AC-Delco Carburetor Tune-Up Conditioner).
NOTICE: DO NOT EXCEED THE 5% CONCENTRATION. AND DO NOT ADD GM TOP ENGINE CLEANER OR AC-DELCO CARBURETOR TUNE-UP CONDITIONER TO VEHICLE GASOLINE TANK, AS DAMAGE TO THE FUEL SYSTEM MAY RESULT.
Equipment manufacturer's instructions, for introducing the solution to the fuel rail may vary. However, the following procedure is recommended for the GM port fuel injection system which includes a fuel pressure test connection. If the equipment does not include a fitting for the fuel pressure test connection, follow the cleaning equipment manufacturer's instructions for cleaning injectors.
1. The fuel system must hold pressure for this procedure. If it does not hold pressure, repair as required.
2. Disable the vehicle in-tank fuel pump. The suggested procedure applicable to all vehicles is to disconnect the pump feed wire connector at the tank.
3. Place approximately 1.475L (50 ounces) of the cleaning solution (95% gasoline, 5% Top Engine Cleaner or Carburetor Tune-Up Conditioner) in cleaning equipment storage tank.
4. Set up equipment with feed hose connected to fuel rail pressure test connection. Do Not Exceed 172.375 kPa (25 psi), supply pressure. ---------------------------------------------------
5. Start and run engine at 2000 R.P.M. for approximately 10 minutes.
6. Disconnect cleaning equipment, recap test fitting, and reconnect vehicle fuel pump.
7. Immediately run engine for 5 minutes at 1000/2000 R.P.M. to flush cleaner from fuel rail and injectors.
8. Verify idle quality and check for leaks.
The following Labour Operation is to be used in conjunction with on vehicle cleaning of Port Fuel Injectors:
Eng Labour Code Operation Time Net Item ---- --------- ---- -------- J, S, W, 9 (2.8L), L T1143 .8 Hr. $2.00 B, 3, 7, 9,(3.8L), F,8
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.
