HIGH IDLE SPEED/HIGH THROTTLE PEDAL EFFORT ON COLD STARTUP

SUBJECT: HIGH IDLE SPEED/HIGH THROTTLE PEDAL EFFORT ON COLD START-UP AT VERY COLD AMBIENT TEMPERATURES (RE-DIRECT P.C.V. VAPORS AT AIR FILTER)

MODELS: 1988-91 OPTIMA 1988-93 PONTIAC LEMANS 1993 ASUNA SE AND GT

CONDITION:

IT IS POSSIBLE UNDER CERTAIN OPERATING CONDITIONS (I.E. VERY COLD AMBIENT TEMPERATURES) THAT HIGH IDLE SPEED AT COLD START WILL NOT RETURN TO NORMAL IDLE SPEED DURING ENGINE WARM-UP.

CAUSE:

CERTAIN DRIVING PATTERNS MAY CAUSE HIGH WATER CONDENSATION IN THE CRANKCASE. THIS WATER IS DRAWN THROUGH THE P.C.V. SYSTEM, INTO THE AIR FILTER, AND DIRECTED INTO THE THROTTLE BODY. UNDER SOME CONDITIONS AT VERY LOW AMBIENT TEMPERATURES, THE WATER CAN FREEZE IN THE THROTTLE BODY AREA AND RESTRICT NORMAL MOVEMENT OF THE THROTTLE.

CORRECTION:

TO CORRECT THIS CONDITION, THE AIR FILTER HOUSING MUST BE MODIFIED TO RE-DIRECT THE INCOMING VAPORS FROM THE P.C.V. SYSTEM. 1.REMOVE AIR FILTER ASSEMBLY FROM VEHICLE. 2.INSTALL P.C.V. OUTLET BLOCK-OFF PLATE, P/N 52367192, AS SHOWN IN FIGURE #1 AND SECURE WITH POP RIVET, P/N 9441669 OR EQUIVALENT. 3.DRILL A 12 MM (1/2") DIAMETER HOLE IN THE SIDE OF THE P.C.V. HOUSING, APPROXIMATELY 150 DEGREES COUNTERCLOCKWISE FROM EXISTING HOLE IN OUTLET AS SHOWN IN FIGURE #2. A SMALLER DIAMETER PILOT HOLE SHOULD BE DRILLED FIRST. 4.REMOVE ALL DRILL HOLE FLASHINGS FROM HOUSING. 5.INSPECT AIR FILTER HOUSING THERMAC MECHANISM FOR CORRECT OPERATION. 6.RE-INSTALL AIR FILTER ASSEMBLY.

SERVICE PARTS INFORMATION: PART # DESCRIPTION QUANTITY 52367192 PLATE 1 9441669 RIVET 1

WARRANTY INFORMATION:

LABOUR OPERATION NUMBER: T8525 LABOUR TIME INFORMATION: 0.2 HOURS

FIGURES: 2

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