ECD SYSTEM(w/ DPF), Diagnostic DTC:P0088

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

DESCRIPTION

P0088
DTC Detection Drive Pattern DTC Detection Condition Trouble Area
After idling for 60 seconds, quickly increase engine speed to 2500 rpm repeatedly for 30 seconds

The fuel pressure of the common rail exceeds 250000 kPa (2350 kgf/cm2, 36250 psi).

(1 trip detection logic)

  • Suction control valve (fuel supply pump assembly)

  • Open or short in suction control valve circuit

  • Fuel pressure sensor (common rail assembly (for bank 1))

  • ECM
Related Data List
DTC No. Data List
P0088

  • Common Rail Pressure

  • Target Common Rail Pressure

  • Target Pump SCV Current

Tech Tips


  • For more information on the fuel supply pump assembly (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 assembly by entering the following menus: Engine and ECT / Data List / Common Rail Pressure.

    Reference
    Engine Speed Common Rail Pressure
    Idling Approximately 27000 to 49000 kPa
    3000 rpm (No engine load) Approximately 57000 to 77000 kPa

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

MONITOR DESCRIPTION


WIRING DIAGRAM

A01X6P6E07

CAUTION / NOTICE / HINT

Note


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

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

  • After replacing an injector assembly, the ECM needs registration 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 FOR 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: Engine and ECT / Trouble Codes.

    4. Read Current DTCs.

      Result
      Result Proceed to
      P0088 is output A
      P0088 and "P0190, P0192 or P0193" are output B

      Tech Tips

      When there is an open circuit in the fuel pressure sensor circuit, the fuel pressure sensor outputs the maximum value. Therefore, P0088 may be stored together with DTCs which indicate common rail fuel pressure sensor circuit malfunctions.


    B

    GO TO FUEL RAIL PRESSURE SENSOR CIRCUIT Click here

    A

  2. CHECK FREEZE FRAME DATA (COMMON RAIL PRESSURE)


    1. Connect the GTS to the DLC3.

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

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

    4. Record the stored DTCs and freeze frame data.

      Result
      Result Proceed to
      Value of Common Rail Pressure is shifting towards 160000 kPa or higher in 3rd and 4th set of freeze frame data B
      Except above A

    B

    REPLACE FUEL SUPPLY PUMP ASSEMBLY (SUCTION CONTROL VALVE) Click here

    A

  3. CHECK WIRE HARNESS (FUEL PRESSURE SENSOR AND ECM)

    Tech Tips

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

    A01X3MNE02
    Text in Illustration
    *1 Engine *2 Engine Wire
    *3

    Common Rail Assembly (for Bank 1)

    (Fuel Pressure Sensor)

    		 *4 Wire to Wire
    *5 ECM - -
    *a Vibration Method (Reference) - -

    1. Check if the MIL lights up when vibration is applied to the wire harness and connectors between the fuel pressure sensor and ECM.

      Result
      Result Proceed to
      MIL does not come on A
      MIL comes on B

    B

    REPAIR OR REPLACE HARNESS OR CONNECTOR Click here

    A

  4. REPLACE FUEL SUPPLY PUMP ASSEMBLY (SUCTION CONTROL VALVE)


    1. Replace the fuel supply pump assembly Click here.

      Tech Tips

      Before replacing the fuel 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 802 to 1202 mA when idling, and outside the range of 840 to 1240 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 fuel supply pump assembly.


    NEXT

  5. BLEED AIR FROM FUEL SYSTEM


    1. Bleed the air from the fuel system Click here.

    2. Perform PM forced regeneration Click here.

      Tech Tips

      When fuel lines are disconnected, air may enter the fuel lines, leading to engine starting trouble. Therefore, perform forced regeneration and bleed the air from the fuel lines.


    NEXT

  6. PERFORM SUPPLY PUMP INITIALIZATION


    1. Perform supply pump initialization Click here.


    NEXT

  7. CHECK DTC OUTPUT


    1. Connect the GTS to the DLC3.

    2. Clear the DTCs Click here.

    3. Turn the ignition switch off for 30 seconds or more.

    4. Turn the ignition switch to ON and start the engine.

    5. After idling for 60 seconds, increase the engine speed from idling to 2500 rpm repeatedly for 30 seconds.

    6. 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: Engine and ECT / Utility / All Readiness.

      2. Input DTC P0088.

      3. Check the DTC judgment result.

        Result
        GTS Display Result Proceed to
        Pending 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.


    NEXT

    CONFIRM WHETHER MALFUNCTION HAS BEEN SUCCESSFULLY REPAIRED Click here

  9. REPAIR OR REPLACE HARNESS OR CONNECTOR


    1. Repair or replace the harness or connector.


    NEXT

  10. CHECK WIRE HARNESS (FUEL PRESSURE SENSOR AND ECM)

    Tech Tips

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

    A01X3MNE02
    Text in Illustration
    *1 Engine *2 Engine Wire
    *3

    Common Rail Assembly (for Bank 1)

    (Fuel Pressure Sensor)

    		 *4 Wire to Wire
    *5 ECM - -
    *a Vibration Method (Reference) - -

    1. Check if the MIL lights up when vibration is applied to the wire harness and connectors between the fuel pressure sensor and ECM.

      Result
      Result Proceed to
      MIL does not come on A
      MIL comes on B

    B

    CONFIRM WHETHER MALFUNCTION HAS BEEN SUCCESSFULLY REPAIRED Click here

    A

  11. REPLACE COMMON RAIL ASSEMBLY (FOR BANK 1) (FUEL PRESSURE SENSOR)


    1. Replace the common rail assembly (for bank 1) Click here.


    NEXT

  12. BLEED AIR FROM FUEL SYSTEM


    1. Bleed the air from the fuel system Click here.

    2. Perform PM forced regeneration Click here.

      Tech Tips

      When fuel lines are disconnected, air may enter the fuel lines, leading to engine starting trouble. Therefore, perform forced regeneration and bleed the air from the fuel lines.


    NEXT

  13. CONFIRM WHETHER MALFUNCTION HAS BEEN SUCCESSFULLY REPAIRED


    1. Connect the GTS to the DLC3.

    2. Clear the DTCs Click here.

    3. Turn the ignition switch off for 30 seconds or more.

    4. Turn the ignition switch to ON and start the engine.

    5. After idling for 60 seconds, increase the engine speed from idling to 2500 rpm repeatedly for 30 seconds.

    6. 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: Engine and ECT / Utility / All Readiness.

      2. Input DTC P0088.

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


    NEXT

    END