SFI SYSTEM, Diagnostic DTC:P0087

DTC Code DTC Name
P0087 Fuel Rail / System Pressure - Too Low

DESCRIPTION

The high-pressure direct injection fuel system consists of a spill control valve, check valve, relief valve and pump plunger. The spill control valve adjusts the return volume of the 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) is installed to the cylinder head cover and operated by a cam installed to the rear end of the intake camshaft. Rotation of the camshaft moves the pump plunger inside the fuel pump (for high pressure) 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 2.75 and 18 MPa (28 and 184 kgf/cm2) and monitors signals from the fuel pressure sensor to maintain the target fuel pressure.

DTC No. Detection Item DTC Detection Condition Trouble Area MIL Memory
P0087 Fuel Rail / System Pressure - Too Low

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

  • Leak of fuel

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

  • Fuel pipe (Fuel pump [for high pressure] - Fuel injector set [for direct injection])

  • Fuel injector set (for direct injection)

  • Fuel pump (for high pressure)

  • Injector driver (EDU)

  • Fuel pump (for low pressure)

  • Fuel pressure sensor

  • ECM

 Comes on DTC stored

MONITOR DESCRIPTION

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

MONITOR STRATEGY

Frequency of Operation Continuous

CONFIRMATION DRIVING PATTERN


  1. Connect the GTS to the DLC3.

  2. Turn the power 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 power switch off and wait for at least 30 seconds.

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

  7. Put the engine in inspection mode (maintenance mode).

    Click here

  8. Start the engine.

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

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

  11. 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.

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

  13. Input the DTC: P0087.

  14. 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.
      Result
      Proceed to
      OK
      NG

    NG

    REPAIR OR REPLACE FUEL LEAK POINT

    OK

  2. CHECK OTHER DTCS OUTPUT (IN ADDITION TO DTC P0087)


    1. Connect the GTS to the DLC3.

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

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

    4. Read the DTCs.


      Powertrain > Engine and ECT > Trouble Codes
      Result
      Result Proceed to
      DTC P0087 is output A
      DTC P0087 and other DTCs are output B

      Tech Tips

      If any DTCs other than P0087 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?

      Result
      Proceed to
      YES
      NO

    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 power switch on (IG).

    3. Turn the GTS on.

    4. Put the engine in inspection mode (maintenance mode).

      Click here


      Powertrain > Hybrid Control > Utility
      Tester Display
      Inspection Mode

    5. Start the engine and warm it up.

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


      Powertrain > Engine and ECT > Active Test
      Active Test Display
      Control the Injection Way
      Data List Display
      Injection Way
      Cylinder #1 Misfire Count
      Cylinder #2 Misfire Count
      Cylinder #3 Misfire Count
      Cylinder #4 Misfire Count

    7. Monitor all of the Misfire Count that are displayed on the GTS.

      Result
      Injection Way 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 set (for direct injection).

      Click here


    B

    REPLACE FUEL INJECTOR SET (FOR DIRECT INJECTION) Click here

    A

  5. CHECK FUEL PRESSURE SENSOR


    1. Connect the GTS to the DLC3.

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

    3. Put the engine in inspection mode (maintenance mode).

      Click here


      Powertrain > Hybrid Control > Utility
      Tester Display
      Inspection Mode

    4. Start the engine.

    5. Enter the following menus: Powertrain / Engine and ECT / Active Test / Control the Target Fuel Pressure / Data List / Fuel Press.


      Powertrain > Engine and ECT > Active Test
      Active Test Display
      Control the Target Fuel Pressure
      Data List Display
      Fuel Press

    6. Check that the fuel pressure fluctuates when the target fuel pressure changes.

      Tech Tips

      The Active Test operation lowers the target fuel pressure by 12.5% or increase the target fuel pressure by 24.8%.

      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 SUB-ASSEMBLY (FUEL PRESSURE SENSOR) Click here

    C

    GO TO STEP 8 Click here

    A

  6. CHECK FUEL PUMP OPERATION (LOW PRESSURE SIDE)


    1. Check the fuel pump operation.

      Click here

      Result
      Proceed to
      OK
      NG

    NG

    GO TO FUEL PUMP CONTROL CIRCUIT Click here

    OK

  7. CHECK FUEL PRESSURE (FOR LOW PRESSURE)


    1. Check the fuel pressure (for low pressure).

      Click here

      Result
      Proceed to
      OK
      NG

    NG

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

    OK

  8. REPLACE INJECTOR DRIVER (EDU)


    1. Replace the injector driver (EDU).

      Click here

      Result
      Proceed to
      NEXT

    NEXT

  9. CHECK IF DTC OUTPUT RECURS (SEE IF DTC P0087 IS OUTPUT AGAIN)


    1. Connect the GTS to the DLC3.

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

    3. Clear the DTCs.


      Powertrain > Engine and ECT > Clear DTCs

    4. Turn the power switch off and wait for at least 30 seconds.

    5. Turn the power switch on (IG) and turn the GTS on.

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

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

    8. Read the DTCs.


      Powertrain > Engine and ECT > Trouble Codes
      Result
      Result Proceed to
      DTC P0087 is output A
      DTCs are not output B

    B

    END

    A

  10. REPLACE FUEL PUMP (FOR HIGH PRESSURE)


    1. Replace the fuel pump (for high pressure).

      Click here

      Tech Tips

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

      Click here

      Result
      Proceed to
      NEXT

    NEXT

  11. CHECK IF DTC OUTPUT RECURS (SEE IF DTC P0087 IS OUTPUT AGAIN)


    1. Connect the GTS to the DLC3.

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

    3. Clear the DTCs.


      Powertrain > Engine and ECT > Clear DTCs

    4. Turn the power switch off and wait for at least 30 seconds.

    5. Turn the power switch on (IG) and turn the GTS on.

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

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

    8. Read the DTCs.


      Powertrain > Engine and ECT > Trouble Codes
      Result
      Result Proceed to
      DTC P0087 is output A
      DTCs are not output B

    A

    REPLACE ECM Click here

    B

    END