For 1990-2009 cars

# DIESEL PLUGGED NOZZLES ADD DEXRON(TYPE 'R')II TO FUEL

DIESEL INJECTION POPPET TYPE NOZZLES ON SOME 1980-83 MODELS MAY BECOME PLUGGED WITH CARBON TO THE POINT WHERE PERFORMANCE MAY BE AFFECTED. THIS MAY SHOW UP AS A ROUGH IDLE, SMOKE, REDUCED PERFORMANCE, LOSS OF FUEL ECONOMY, ETC. POPPET NOZZLES USED ON 1984- 85 MODELS ARE OF SEMI GUIDED DESIGN, AND HAVE NOT SHOWN A TENDENCY TO PLUG. THE PLUGGING CONDITION CAN BE GREATLY REDUCED IF NOT ELIMINATED WITH THE ADDITION OF DEXRON "R" II AUTOMATIC TRANSMISSION FLUID TO THE DIESEL FUEL. ADD TWO QUARTS TO DEXRON "R" II AUTOMATIC TRANSMISSION FLUID TO THE FUEL TANK, THEN FILL WITH DIESEL FUEL. ADVISE THE CUSTOMER TO DRIVE THE VEHICLE UNTIL THE FUEL LEVEL IS LESS THAN 1/4 TANK BEFORE ADDING ADDITIONAL DIESEL FUEL. DO NOT ADD ADDITIONAL TRANSMISSION FLUID. IF CARBON ACCUMULATION WAS RESPONSIBLE FOR THE DRIVEABILITY CONDITION, THIS PROCEDURE SHOULD CORRECT IT. IF THE CONDITION IS NOT CORRECTED, ADDITIONAL QUANTITIES OF TRANSMISSION FLUID WILL NOT CORRECT CONDITION.

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.