SFI SYSTEM, Diagnostic DTC:P008700

DTC Code DTC Name
P008700 Fuel Rail / System Pressure - Too Low

DESCRIPTION

The high-pressure direct injection fuel system consists of a spill control valve, check valve, fuel relief valve, fuel pressure sensor, fuel pump (for high pressure side) and fuel injector assemblies (for direct injection). The spill control valve adjusts the return volume of high-pressure fuel. The check valve mechanically opens and closes the paths to the fuel delivery pipes. The relief valve releases the fuel back to the fuel tank if the high-pressure fuel system malfunctions. The fuel pump (for high pressure side) is installed to the cylinder head cover and operated by a cam installed to the end of the intake camshaft.

Rotation of the camshaft moves the pump plunger inside the fuel pump (for high pressure side) up and down, pressurizing the fuel. The pressurized fuel opens the check valve and is pumped into the fuel delivery pipe. The ECM controls the spill control valve to adjust the fuel pressure between 2 and 25 MPa (20 and 255 kgf/cm2) and monitors signals from the fuel pressure sensor to maintain the target fuel pressure.

A01W1JEE02
Text in Illustration
*1

ECM

- Injector Driver Unit

 *2 Fuel Injector Assembly (for Port Injection)
*3 Fuel Injector Assembly (for Direct Injection) *4 Fuel Pressure Sensor
*5 Spill Control Valve *6 Pulsation Damper
*7 Check Valve *8 Fuel Relief Valve
*9 Fuel Pump (for High Pressure Side) *10 Intake Camshaft
*11 Pressure Regulator *12 Fuel Pump (for Low Pressure Side)
*13 Fuel Tank - -
*a Low Pressure Fuel Line *b Return Fuel Line
*c High Pressure Fuel Line - -
DTC No. DTC Detection Condition Trouble Area
P008700

Although the ECM is not requesting the fuel pump (for high pressure side) to open the spill control valve, fuel pressure decreases 5 MPa (51.0 kgf/cm2, 725 psi) from target pressure for about 10 seconds (1 trip detection logic).

  • Leak of fuel

  • Fuel pipe (fuel tank - fuel pump [for high pressure side])

  • Fuel pipe (fuel pump [for high pressure side] - fuel injector assembly [for direct injection])

  • Fuel injector assembly (for direct injection)

  • Fuel pump (for high pressure side)

  • Fuel pump (for low pressure side)

  • Fuel pressure sensor

  • Fuel system

  • ECM

MONITOR DESCRIPTION

If the fuel pressure decreases despite an increase request signal being sent to the fuel pump (for high pressure side) by the ECM, the ECM will illuminate the MIL and store this DTC.

MONITOR STRATEGY

Required Sensors/Components Fuel pressure sensor
Frequency of Operation Continuous

CONFIRMATION DRIVING PATTERN


  1. Connect the GTS to the DLC3.

  2. Turn the engine switch on (IG) and turn the GTS on.

  3. Record the freeze frame data.

  4. Clear the DTCs (even if no DTCs are stored, perform the clear DTC procedure).

  5. Turn the engine switch off and wait for at least 30 seconds.

  6. Turn the engine switch on (IG) and turn the GTS on.

  7. Start the engine.

  8. Based on engine speed, engine load and other freeze frame data stored in the ECM, reproduce the conditions present when the DTC was stored.

  9. Enter the following menus: Powertrain / Engine / Trouble Codes.

  10. Read the pending DTCs.

    Tech Tips


    • If a pending DTC is output, the system is malfunctioning.

    • If a pending DTC is not output, perform the following procedure.

  11. Enter the following menus: Powertrain / Engine / Utility / All Readiness.

  12. Input the DTC: P008700.

  13. Check the DTC judgment result.

    GTS Display Description
    NORMAL

    • DTC judgment completed

    • System normal
    ABNORMAL

    • DTC judgment completed

    • System abnormal
    INCOMPLETE

    • DTC judgment not completed

    • Perform driving pattern after confirming DTC enabling conditions
    N/A

    • Unable to perform DTC judgment

    • Number of DTCs which do not fulfill DTC preconditions has reached ECU memory limit

    Tech Tips


    • If the judgment result shows NORMAL, the system is normal.

    • If the judgment result shows ABNORMAL, the system has a malfunction.

    • If the judgment result shows INCOMPLETE or N/A, perform the Confirmation Driving Pattern and check the DTC judgment result again.

CAUTION / NOTICE / HINT

Tech Tips

Read freeze frame data using the GTS. The ECM records vehicle and driving condition information as freeze frame data the moment a DTC is stored. When troubleshooting, freeze frame data can help determine if the vehicle was moving or stationary, if the engine was warmed up or not, if the air fuel ratio was lean or rich, and other data from the time the malfunction occurred.

PROCEDURE


  1. CHECK FUEL LEAK


    1. Check around and beneath the car for fuel leaks, fumes, etc.

      OK
      No fuel leaks present.

    NG

    REPAIR OR REPLACE FUEL LEAK POINT

    OK

  2. CHECK OTHER DTCS OUTPUT (IN ADDITION TO DTC P008700)


    1. Connect the GTS to the DLC3.

    2. Turn the engine switch on (IG).

    3. Turn the GTS on.

    4. Enter the following menus: Powertrain / Engine / Trouble Codes.

    5. Read the DTCs.

      Result
      Result Proceed to
      DTC P008700 is output A
      DTC P008700 and other DTCs are output B

      Tech Tips

      If any DTCs other than P008700 are output, troubleshoot those DTCs first.


    B

    GO TO DTC CHART Click here

    A

  3. CONFIRM IF VEHICLE HAS RUN OUT OF FUEL IN PAST


    1. Has the vehicle run out of fuel in the past?


    YES

    DTC CAUSED BY RUNNING OUT OF FUEL

    NO

  4. CHECK MISFIRE COUNT OF DIRECT INJECTION


    1. Connect the GTS to the DLC3.

    2. Turn the engine switch on (IG).

    3. Turn the GTS on.

    4. Start the engine and warm it up.

    5. Enter the following menus: Powertrain / Engine / Active Test / Control the Injection Mode / Direct / Data List / All Data / Injection Mode and Misfire Count Cylinder #1 to Misfire Count Cylinder #4.

      Tech Tips


      • When using the "Control the Injection Mode" Active Test to check the condition of the engine, switch from "Port" to "Direct".

      • Do not switch from "Direct" to "Port". When performing the inspection more than once, after the Active Test ends, lightly race the engine, and then perform the inspection from "Port" again.

      • If the display does not switch from "Port" even after lighting racing the engine, idle the engine for approximately 1 minute, and then lightly race the engine.

    6. Monitor all of the misfire count that are displayed on the GTS.

      Result
      Injection Mode Misfire Count Proceed to
      Direct There are no misfire counts A
      3 cylinders or more have misfire counts
      1 or 2 cylinders have misfire counts B

      Tech Tips

      Perform "Inspection After Repair" after replacing the fuel injector assembly (for direct injection) Click here.


    B

    REPLACE FUEL INJECTOR ASSEMBLY (FOR DIRECT INJECTION) Click here

    A

  5. CHECK FUEL PRESSURE SENSOR


    1. Connect the GTS to the DLC3.

    2. Turn the engine switch on (IG) and turn the GTS on.

    3. Enter the following menus: Powertrain / Engine / Data List / All Data / Fuel Pressure (High).

    4. Start the engine.

    5. Check that the fuel pressure fluctuates when the engine condition changes from idling to racing.

      Result
      Result Proceed to
      Fuel pressure does not rise A
      Fuel pressure does not fluctuate B
      Fuel pressure fluctuates C

    B

    REPLACE FUEL DELIVERY PIPE (FUEL PRESSURE SENSOR) Click here

    C

    REPLACE FUEL PUMP (FOR HIGH PRESSURE SIDE) Click here

    A

  6. CHECK FUEL PUMP OPERATION (FOR LOW PRESSURE SIDE)


    1. Check the fuel pump operation (for low pressure side) Click here.


    NG

    GO TO FUEL PUMP CONTROL CIRCUIT Click here

    OK

  7. CHECK FUEL PRESSURE (FOR LOW PRESSURE SIDE)


    1. Check the fuel pressure (for low pressure side) Click here.


    NG

    REPAIR OR REPLACE FUEL SYSTEM (PRESSURE REGULATOR, PIPE LINE AND FILTER)

    OK

  8. REPLACE FUEL PUMP (FOR HIGH PRESSURE SIDE)


    1. Replace the fuel pump (for high pressure side) Click here.

      Tech Tips

      Perform "Inspection After Repair" after replacing the fuel pump (for high pressure side) Click here.


    NEXT

  9. CHECK IF DTC OUTPUT RECURS (SEE IF DTC P008700 IS OUTPUT AGAIN)


    1. Connect the GTS to the DLC3.

    2. Turn the engine switch on (IG).

    3. Turn the GTS on.

    4. Clear the DTCs.

    5. Turn the engine switch off and wait for at least 30 seconds.

    6. Turn the engine switch on (IG).

    7. Turn the GTS on.

    8. Drive the vehicle in accordance with the driving pattern described in the Confirmation Driving Pattern.

    9. Enter the following menus: Powertrain / Engine / Trouble Codes.

    10. Read the DTCs.

      Result
      Result Proceed to
      DTC P008700 is output A
      DTCs are not output B

    A

    REPLACE ECM Click here

    B

    END