EXCESSIVE OIL CONSUMPTION (REPLACE PCV HARNESS). Pontiac Grand Prix 1993

SUBJECT: EXCESSIVE OIL CONSUMPTION (REPLACE PCV HARNESS)

MODELS: 1991-95 CHEVROLET LUMINA, MONTE CARLO 1991-95 OLDSMOBILE CUTLASS SUPREME 1991-95 PONTIAC GRAND PRIX WITH 3.4L TWIN DOHC ENGINE (VIN X--RPO LQ1)

CONDITION:

SOME OWNERS MAY EXPERIENCE EXCESSIVE CONSUMPTION OF ENGINE OIL. EXCESSIVE OIL USAGE IS DEFINED AS THE CONSUMPTION OF 0.95L (1 QT) OR MORE OF ENGINE OIL WITHIN 2,000 MILES OR 3,200 KILOMETERS.

CAUSE:

IT HAS BEEN DETERMINED THAT ENGINE OIL IS BEING INTRODUCED INTO THE POSITIVE CRANKCASE VENTILATION SYSTEM (PCV) AND THEN INGESTED INTO THE ENGINE AND BURNT. TYPICALLY THERE IS NO SMOKE EVIDENT FROM THE VEHICLE'S TAILPIPE DUE TO THE EFFICIENCY OF THE CATALYTIC CONVERTER. IT IS ALSO IMPORTANT TO NOTE THAT TO PROPERLY CHECK THE ENGINE OIL LEVEL ON A VEHICLE THAT HAS REACHED OPERATING TEMPERATURE THAT THERE IS A REQUIRED 20 MINUTE WAITING PERIOD (ENGINE NOT RUNNING) WHICH WILL ALLOW THE OIL FROM THE OVERHEAD TO PROPERLY DRAIN BACK INTO THE CRANKCASE. FAILURE TO DO SO COULD RESULT IN AN IMPROPER OIL LEVEL READING.

CORRECTION:

THE CAUSE FOR EXCESSIVE OIL CONSUMPTION NOT DUE TO LEAKS FIRST MUST BE DETERMINED. OIL CONSUMPTION MAY RESULT FROM ONE OR MORE OF THE FOLLOWING CONDITIONS: - IMPROPER READING OF THE OIL INDICATOR. CHECK THE OIL ON A LEVEL SURFACE AND ALLOW A MINIMUM OF 20 MINUTES FOR DRAIN-DOWN ON A HOT ENGINE OIL. - IMPROPER OIL FILL AFTER AN OIL CHANGE. THE RECOMMENDED OIL FILL CAPACITY IS 5.5 QTS (5.2L) WITH OIL FILTER PF52. - IMPROPER OIL VISCOSITY. FOR 1991-95, USE SAE 5W30 VISCOSITY OIL. - EXTERNAL OIL LEAKS. - CONTINUOUS HIGH SPEED DRIVING, AND/OR SEVERE USAGE SUCH AS TRAILER TOWING WILL REDUCE OIL ECONOMY. - CRANKCASE VENTILATION. - PISTON SCUFFING. - EXCESSIVE PISTON TO CYLINDER WALL CLEARANCE. - WORN OR BROKEN PISTON RINGS. - WORN VALVE GUIDES AND OR VALVE STEM SEALS. - INADEQUATE SEALING OF VALVE FACE TO VALVE SEAT.

IF THE ITEMS ABOVE HAVE BEEN CHECKED AND FOUND TO BE IN SATISFACTORY CONDITION, THEN IT WILL BE NECESSARY TO REPLACE THE FRESH AND FOUL AIR SIDES OF THE PCV SYSTEM. THIS CAN BE ACCOMPLISHED BY PERFORMING THE FOLLOWING PROCEDURE.

1. REMOVE THE FUEL INJECTION SIGHT SHIELD. 2. REMOVE THE FRONT SPARK PLUG WIRES. 3. REMOVE THE FRONT CAM COVER AND REPLACE WITH NEW COVER, P/N 24505197. TIGHTEN BOLTS TO 11 NM (97 LB. IN.). 4. INSTALL NEW OIL FILL CAP, P/N 12551958. 5. REMOVE THE PCV SYSTEM EMISSION HARNESS AND INSTALL NEW HARNESS, P/N 24507504. 6. INSTALL NEW PCV VALVE, P/N 25095452. ON 1991-93 VEHICLES, REMOVE PCV HOSE AT UPPER MANIFOLD INLET AND REPLACE WITH P/N 24503122. 7. INSTALL NEW SPARK PLUG WIRES AND REUSE THE WIRE RETAINER CLIP FOR CYLINDERS 2-4-6. REMOVE THE SPARK PLUG WIRE RETAINER CLIP FROM THE METAL BRACKET AND REUSE JUST THE CLIP PORTION. 8. REINSTALL THE FUEL INJECTOR SIGHT SHIELD.

PARTS INFORMATION:

PARTS WILL BE AVAILABLE FROM GMSPO ON 1/13/97.

PART NUMBER PART DESCRIPTION QUANTITY

24507504 EMISSION HARNESS 1

24505197 LEFT CAM COVER 1 (INCLUDES GASKET)

25095452(CV895C) PCV VALVE 1

24503122 PCV HOSE (1991-1993 ONLY) 1

12173565 S/PLUG WIRE CYL. # 2 1

12173565 S/PLUG WIRE CYL. # 4 1

12173567 S/PLUG WIRE CYL. # 6 1

12551958 OIL FILL CAP 1

WARRANTY INFORMATION:

FOR VEHICLES REPAIRED UNDER WARRANTY, USE:

LABOR CODE: J6000 VALVE, PCV - REPLACE

LABOR TIME: 0.2 HR ADD 0.5 HR INSTALL OIL CONSUMPTION KIT

FIGURES: 0 ATTACHMENTS: 0

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.