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HOMESERVICE MANUALSFORD2004PICKUP F350 SUPER DUTY, 4D PICKUP, 6.8 S, RWD, AUTOMATICREPAIR AND DIAGNOSIS (SINGLE PAGE)ENGINE PERFORMANCESYSTEMENGINE CONTROLS - PINPOINT TEST DX: ENGINE COOLANT TEMPERATURE (ECT) SENSOR THROUGH PINPOINT TEST HC: FUEL DELIVERY SYSTEM - CNG, FLEX-FUEL & GASOLINEPINPOINT TEST HC: FUEL DELIVERY SYSTEMTEST PROCEDURE
2004 Ford Pickup F350 Super Duty, 4D Pickup, 6.8 S, RWD, Automatic

Test Procedure

2004 Ford Pickup F350 Super Duty, 4D Pickup, 6.8 S, RWD, AutomaticSECTION Test Procedure
NOTE: Proceed to DTC testing steps listed in FAULT CODE SETTING CONDITION  table of fault code setting condition.
FAULT CODE SETTING CONDITION

Fault Code KOEO KOER Continuous Memory
P0148      HC1
  1. HC1 CHECK THE SYSTEM INTEGRITY 
    • Visually inspect the complete fuel delivery system for damage and leakage.
    • Check the following:
      • Fuel lines and connections.
      • Relays.
      • Fuel tank.
      • Fuel pump.
      • Fuel pressure regulator.
      • Fuel pulse damper.
      • Fuel rail at injectors.
      • Damaged connector pins.
      • Electrical connectors not fully engaged.
    • Verify the vehicle has followed the maintenance schedule. (Fuel filter should have been replaced within the last 48,280 km (30,000 miles)).
    • VERIFY the Inertia Fuel Shutoff (IFS) switch is set (button pushed in). REFER to the Owner Guide for location.
    • Verify the fuse integrity.
    • Verify the battery is fully charged.
    • Verify clean sufficient fuel.

    Are any of the above concerns present? 

    Yes No
    REPAIR as necessary. GO to  HC2.
  2. HC2 CHECK ALL SYSTEM RELATED DEVICES (SENSOR, DAMPER OR REGULATOR) FOR LEAKAGE 
    • Key in OFF position.
    • FP connector connected.
    • Key ON, engine running.
    • Check for manifold vacuum at each system related component with a vacuum line.
    • Key in OFF position.
    • Wait 10 seconds.
    • Key ON, engine running.
    • Run the engine for approximately 10 seconds.
    • Key in OFF position.
    • Remove the vacuum hose on each system device connected to the fuel rail.
    • Inspect for the presence of fuel in the vacuum line of each device connected to the fuel rail.

    Are all vacuum lines for system related devices indicating no fuel present? 

    Yes No
    GO to  HC3. If the vacuum line connected to a component indicates that a fuel leak is present, INSTALL a new component.
  3. HC3 CHECK THE FUEL PRESSURE 
    WARNING: BEFORE SERVICING OR REPLACING ANY COMPONENTS IN THE FUEL SYSTEM, REDUCE THE POSSIBILITY OF INJURY OR FIRE BY FOLLOWING THE WARNING, CAUTION, AND HANDLING DIRECTIONS IN SAFE FUEL HANDLING PRACTICES: GASOLINE, METHANOL, AND METHANOL BLENDS  AT BEGINNING OF THIS PINPOINT TEST.
    • Key in OFF position.
    • Relieve the fuel pressure. Refer to the appropriate FUEL SYSTEM article for the Fuel System Pressure Release procedure.
    • Mechanical fuel pressure gauge connected.
    • Key ON, engine OFF.
    • Pressurize the fuel system. Refer to the appropriate FUEL SYSTEM article for Fuel System for the Fuel System Pressure Release procedure.
    • Compare the fuel pressure reading to the Fuel System Specification Chart.

    Is the fuel pressure within range? 

    Yes No
    GO to  HC6. GO to  HC4.
  4. HC4 CHECK THE VOLTAGE AT THE FUEL PUMP HARNESS CONNECTOR 
    • FP connector disconnected.
      NOTE: REFER to the appropriate SYSTEM WIRING DIAGRAMS article for correct pin location.
    • Measure the voltage between:
      ( + ) Vehicle Battery ( - ) FP Connector, Harness Side
      Positive terminal FPGND

    Is the voltage greater than 10 V? 

    Yes No
    GO to  HC5. Key in OFF position. REPAIR the open circuit.
  5. HC5 CHECK THE VOLTAGE AT THE FUEL PUMP HARNESS CONNECTOR 
    • VERIFY the Inertia Fuel Shutoff (IFS) switch is set (button pushed in). REFER to the Owner Guide for location.
    • FP connector disconnected.
    • Key ON, engine OFF.
    • Access the PCM and control the FP PID.
    • Be aware that Output Test Mode turns off the FP after a calibrated time. If this happens, command the outputs on again to continue testing.
    • Measure the voltage between:
      ( + ) FP Connector, Harness Side ( - ) Vehicle Battery
      FPPWR Negative terminal

    Is the voltage greater than 10 V? 

    Yes No
    Key in OFF position.
    EXIT the Output State Control.
    GO to  HC6.    		 Key in OFF position. REPAIR the open circuit.
  6. HC6 CHECK THE FUEL PRESSURE LEAKDOWN 
    NOTE: When the fuel pump is commanded off, the fuel pressure may substantially decrease and then stabilize.
RENDER: 1.0x

NO RELATED

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When to See a Mechanic

Stop DIY work and contact a certified mechanic immediately if any of the following apply:

  • • You smell fuel, burning insulation, or see smoke.
  • • Brakes feel soft, pull hard to one side, or make grinding noises.
  • • The engine overheats, stalls repeatedly, or misfires under load.
  • • You are missing required tools, torque specs, or safe lifting equipment.
  • • You are not confident in the next step or safety outcome.