ECD SYSTEM(for DPF), Diagnostic DTC:P0088

DTC Code DTC Name
P0088 Fuel Rail / System Pressure - Too High

DESCRIPTION

DTC No. Detection Item DTC Detection Condition Trouble Area MIL Memory
P0088 Fuel Rail / System Pressure - Too High

The fuel pressure of the common rail exceeds 220000 kPa (2243.4 kgf/cm2, 31900 psi).

(1 trip detection logic)

  • Supply pump assembly (suction control valve)

  • Pressure discharge valve (built into common rail assembly)

  • Open or short in supply pump assembly (suction control valve) circuit

  • Fuel pressure sensor (built into common rail assembly)

  • ECM

 Comes on DTC stored
Related Data List
DTC No. Data List
P0088

  • Fuel Press

  • Target Common Rail Pressure

  • Injection Pressure Correction

  • Target Pump SCV Current

  • Pressure Discharge Valve

Tech Tips


  • For more information on the fuel supply pump (suction control valve) and common rail system, refer to System Description Click here.

  • When DTC P0088 is stored, check the internal fuel pressure of the common rail by entering the following menus: Powertrain / Engine and ECT / Data List / Fuel Press.

    Reference
    Engine Speed Fuel Press
    Idling Approximately 27000 to 45000 kPa
    3000 rpm (No engine load) Approximately 45000 to 78000 kPa

  • When there is an operating problem with the fuel supply pump (when Fuel Press is more than Target Common Rail Pressure due to a problem with the closing of the suction valve), the values of Injection Pressure Correction and Target Pump SCV Current decrease.

  • Check "Fuel Press", "Target Common Rail Pressure", "Target Pump SCV Current" and "Pressure Discharge Valve" in the freeze frame data.

MONITOR DESCRIPTION


CONFIRMATION DRIVING PATTERN

DTC No. DTC Detection Drive Pattern
P0088 After idling for 60 seconds, repeat quick engine speed accelerations (from idling to 2500 rpm) for 30 seconds

WIRING DIAGRAM

A01QPLGE01
*a Suction Control Valve

CAUTION / NOTICE / HINT

Note


  • After replacing the ECM, the new ECM needs registration (Click here ) and initialization Click here.

  • After replacing the fuel supply pump, the ECM needs initialization Click here.

Tech Tips

Read freeze frame data using the GTS. Freeze frame data records the engine condition when malfunctions are detected. When troubleshooting, freeze frame data can help determine if the vehicle was moving or stationary, if the engine was warmed up or not, and other data from the time the malfunction occurred.

PROCEDURE


  1. CHECK ANY OTHER DTCS OUTPUT (IN ADDITION TO DTC P0088)


    1. Connect the GTS to the DLC3.

    2. Turn the ignition switch to ON and turn the GTS on.

    3. Enter the following menus: Powertrain / Engine and ECT / Trouble Codes.


      Powertrain > Engine > Trouble Codes

    4. Read Current DTCs.

      Result
      Proceed to
      DTC P0088 is output
      DTC P0088 and other DTCs are output

      Tech Tips

      If any DTCs other than P0088 are output, troubleshoot those DTCs first.


    DTC P0088 and other DTCs are output

    GO TO DTC CHART Click here

    DTC P0088 is output

  2. CHECK FREEZE FRAME DATA (FUEL PRESS)


    1. Connect the GTS to the DLC3.

    2. Turn the ignition switch to ON and turn the GTS on.

    3. Enter the following menus: Powertrain / Engine and ECT / Trouble Codes.


      Powertrain > Engine > Trouble Codes

    4. Record the stored DTC and freeze frame data.

      Result
      Result Proceed to
      Except below A
      Value of Fuel Press is shifting towards 160000 kPa or higher in 3rd and 4th set of freeze frame data B

    B

    GO TO STEP 4 Click here

    A

  3. CHECK HARNESS AND CONNECTOR

    Tech Tips

    If the MIL has illuminated before in the past, clear the DTC using the GTS before performing this inspection.

    Click here

    A01QPHSC01
    *1 Engine *2 Engine Wire
    *3

    Common Rail Assembly

    (Fuel Pressure Sensor)

    		 *4 Wire to Wire
    *5 ECM - -
    *a Vibration Method (Reference) - -
    Result
    Proceed to
    MIL does not come on
    MIL comes on

    MIL comes on

    REPAIR OR REPLACE HARNESS OR CONNECTOR Click here

    MIL does not come on

  4. REPLACE SUCTION CONTROL VALVE


    1. Replace the suction control valve.

      Click here

      Tech Tips

      Before replacing the supply pump assembly, check that the wire harness between the suction control valve and ECM is not shorted to ground.

      When there is a malfunction in the wire harness, Target Pump SCV Current is outside the range of 923 to 1123 mA when idling, and outside the range of 1013 to 1212 mA when the engine is running at 2500 rpm without load.

      If there are no problems with the engine condition during idling, it is not necessary to perform the above wire harness inspection.

      When the wire harness between the suction control valve and ECM is not shorted to ground, it can be assumed that DTC P0088 was stored due to a malfunction in the operation of the suction control valve. Therefore, it is necessary to replace the supply pump assembly.

      Result
      Proceed to
      NEXT

    NEXT

  5. BLEED AIR FROM FUEL SYSTEM


    1. Bleed the air from the fuel system.

      Click here

      Result
      Proceed to
      NEXT

    NEXT

  6. PERFORM SUPPLY PUMP INITIALIZATION


    1. Perform supply pump initialization.

      Click here

      Result
      Proceed to
      NEXT

    NEXT

  7. CHECK DTC OUTPUT


    1. Connect the GTS to the DLC3.

    2. Turn the ignition switch to ON.

    3. Turn the GTS on.

    4. Clear the DTCs.


      Powertrain > Engine > Clear DTCs

    5. Turn the ignition switch off and wait for 30 seconds or more.

    6. Start the engine and turn the GTS on.

    7. After idling for 60 seconds, repeat quick engine speed accelerations (from idling to 2500 rpm) for 30 seconds.

    8. Confirm that the DTC is not output again.

      Tech Tips

      Perform the following procedure using the GTS to determine whether or not the DTC judgment has been carried out.


      1. Enter the following menus: Powertrain / Engine and ECT / Utility / All Readiness.


        Powertrain > Engine > Utility
        Tester Display
        All Readiness

      2. Input DTC P0088.

      3. Check the DTC judgment result.

        Result
        GTS Display Result Proceed to
        Pending DTC DTC P0088 is output A
        All Readiness NORMAL B
        ABNORMAL A

        Tech Tips

        If STATUS is INCOMPLETE or N/A, race the engine to 2500 rpm repeatedly for 30 seconds and increase the idling time.


    B

    END

    A

  8. REPLACE ECM


    1. Replace the ECM.

      Click here

      Result
      Proceed to
      NEXT

    NEXT

    GO TO STEP 13 Click here

  9. REPAIR OR REPLACE HARNESS OR CONNECTOR


    1. Repair or replace the harness or connector.

      Result
      Proceed to
      NEXT

    NEXT

  10. CHECK HARNESS AND CONNECTOR

    Tech Tips

    If the MIL has illuminated before in the past, clear the DTC using the GTS before performing this inspection.

    Click here

    A01QPHSC01
    *1 Engine *2 Engine Wire
    *3

    Common Rail Assembly

    (Fuel Pressure Sensor)

    		 *4 Wire to Wire
    *5 ECM - -
    *a Vibration Method (Reference) - -
    Result
    Proceed to
    MIL does not come on
    MIL comes on

    MIL does not come on

    GO TO STEP 13 Click here

    MIL comes on

  11. REPLACE COMMON RAIL ASSEMBLY


    1. Replace the common rail assembly.

      Click here

      Result
      Proceed to
      NEXT

    NEXT

  12. BLEED AIR FROM FUEL SYSTEM


    1. Bleed the air from the fuel system.

      Click here

      Result
      Proceed to
      NEXT

    NEXT

  13. CONFIRM WHETHER MALFUNCTION HAS BEEN SUCCESSFULLY REPAIRED


    1. Connect the GTS to the DLC3.

    2. Turn the ignition switch to ON.

    3. Turn the GTS on.

    4. Clear the DTCs.


      Powertrain > Engine > Clear DTCs

    5. Turn the ignition switch off and wait for 30 seconds or more.

    6. Start the engine and turn the GTS on.

    7. After idling for 60 seconds, repeat quick engine speed accelerations (from idling to 2500 rpm) for 30 seconds.

    8. Confirm that the DTC is not output again.

      Tech Tips

      Perform the following procedure using the GTS to determine whether or not the DTC judgment has been carried out.


      1. Enter the following menus: Powertrain / Engine and ECT / Utility / All Readiness.


        Powertrain > Engine > Utility
        Tester Display
        All Readiness

      2. Input DTC P0088.

      3. Check that STATUS is NORMAL.

        Tech Tips

        If STATUS is INCOMPLETE or N/A, race the engine to 2500 rpm repeatedly for 30 seconds and increase the idling time.

      Result
      Proceed to
      NEXT

    NEXT

    END