EXTENDED CRANK TIME AFTER COLD START. Cadillac Eldorado 1995

SUBJECT: EXTENDED CRANK TIME AFTER COLD SOAK (DIAGNOSE FOR LOSS OF FUEL PRESSURE)

MODELS: 1993 CADILLAC ALLANTE 1993-95 CADILLAC ELDORADO AND SEVILLE 1994-95 CADILLAC CONCOURS WITH 4.6L NORTHSTAR ENGINE (VINS 9, Y - RPOS L37, LD8)

CONDITION:

SOME OWNERS MAY EXPERIENCE A CONDITION OF EXTENDED CRANKING TIME FOLLOWING A COLD SOAK WITH NO MIL OR MESSAGE.

CAUSE:

THE RESIDUAL FUEL SYSTEM PRESSURE MAY BE DECREASING AFTER TURNING OFF THE IGNITION DUE TO A POOR SEATING FUEL RAIL, INJECTOR O-RING OR FUEL PUMP CHECK VALVE.

CORRECTION:

TO DIAGNOSE THIS CONDITION, INSTALL J34730 FUEL PRESSURE GAGE. KEY ON TO CYCLE THE FUEL PUMP AND NOTE GAGE. THE FUEL SYSTEM SHOULD PRODUCE BETWEEN 40 AND 50 PSI. THE FUEL PRESSURE SHOULD REMAIN AT THAT LEVEL FOR AN EXTENDED PERIOD OF TIME -- AT LEAST 2 HOURS. IF THE FUEL PRESSURE IMMEDIATELY OR GRADUALLY DROPS, A FUEL RAIL LEAKDOWN CONDITION EXISTS. TO CORRECT THIS CONDITION PERFORM THE FOLLOWING PROCEDURES:

1. INSTALL J37287-2 FUEL LINE SHUT OFF ON FUEL RETURN LINE AND TURN VALVE TO THE OFF POSITION.

2. INSTALL J37287-1 FUEL LINE SHUT OFF ON FUEL INLET LINE AND TURN VALVE TO THE "ON" POSITION.

3. RUN FUEL PUMP TO PRESSURIZE SYSTEM.

4. WHEN SYSTEM IS PRESSURIZED, CLOSE VALVE ON THE INLET LINE AND DEENERGIZE THE PUMP.

5. IF FUEL PRESSURE GAUGE INDICATES THAT A LEAKDOWN CONDITION STILL EXISTS, GO TO STEP 6. IF SYSTEM DOES NOT LEAK DOWN, REPLACE FUEL TANK SENDING UNIT BECAUSE THE CHECK VALVE IS LEAKING.

6. DEPRESSURIZE THE FUEL SYSTEM AND REMOVE THE INTAKE MANIFOLD TOP COVER TO INSPECT THE FUEL RAIL FOR SIGNS OF LEAKING (SPLIT RAIL, MISSING/DAMAGED O-RING, ETC.) AND REPAIR ANY LEAKS.

7. IF NO SIGNS OF LEAKING ARE PRESENT, ONE OR MORE INJECTORS ARE THE CAUSE. PERFORM INJECTOR FLOW TEST IN SECTION 6C OF THE SERVICE MANUAL TO DETERMINE WHICH INJECTOR IS LEAKING AND REPLACE.

WARRANTY INFORMATION:

FOR VEHICLES REPAIRED UNDER WARRANTY, USE: LABOR OPERATION: L1200 - SENDING UNIT J5660 - FUEL RAIL USE PUBLISHED LABOR OPERATION TIME. YOU MAY CLAIM 0.0 TO 0.3 HOURS AS DIAGNOSIS TIME. J5650 - FUEL INJECTORS USE PUBLISHED LABOR OPERATION TIME.

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.