LEMON Manuals: Even more car manuals for everyone
Home >> Subaru >> 2020 >> Crosstrek Base, Automatic CVT Trans >> Repair and Diagnosis >> External Pages >> Different variant/trim >> Section 26 (Engine Control System (Diagnostics) (HEV) (1 Of 4)) >> Diagnostic Procedure with Diagnostic Trouble Code (DTC) >> DTC P0087: Fuel Rail/System Pressure - Too Low Bank 1 >> Notes

DTC P0087: Fuel Rail/System Pressure - Too Low Bank 1: Notes

WARNING: This page is about a different variant/trim than selected.
  1. - 

    DTC detecting condition: 

    Immediately at fault recognition

    Trouble symptom: 

    • Improper idling
    • Poor driving performance
    • Poor acceleration
    NOTE: After the faulty parts are repaired or replaced, perform the final check in Basic Diagnostic Procedure. Ref. to ENGINE (DIAGNOSTICS) (H4DO (HEV))>BASIC DIAGNOSTIC PROCEDURE>PROCEDURE .
    G13615158Courtesy of SUBARU OF AMERICA, INC.
    G13615159Courtesy of SUBARU OF AMERICA, INC.
  1. CHECK FOR FUEL DELIVERY LINE LEAKAGE  .

    Visually check the fuel delivery line for leakage.

    WARNING:
    • When checking fuel delivery line during engine operation, be very careful so that one's hair, body and clothes do not touch the rotating part in the engine compartment.
    • If there is fuel leakage, the fuel can be combusted spontaneously by the engine heat, resulting in serious accident. Therefore, take extra care.
    • Prepare the necessary fire-extinguishing appliance for immediate fire fighting in case of fire.
    NOTE: Concerning the section where visible inspection is difficult, the fuel odor provides a good indication of determining the fuel leakage.

    Are there leaks from the fuel delivery line?

    Yes  : Replace the faulty fuel delivery line. Ref. to FUEL INJECTION (FUEL SYSTEMS) (H4DO (HEV))>FUEL DELIVERY AND EVAPORATION LINES . Ref. to FUEL INJECTION (FUEL SYSTEMS) (H4DO (HEV))>FUEL INJECTOR .

    No  : Go to  2.

  2. CHECK DTC  .

    Using the Subaru Select Monitor or a general scan tool, read the DTC of [Engine]. Ref. to COMMON (DIAG)>DIAGNOSTIC TROUBLE CODE (DTC) .

    Is DTC other than P0087 displayed? (Current malfunction)

    Yes  : Check the appropriate DTC using the "Diagnostic Trouble Code (DTC)". Ref. to ENGINE (DIAGNOSTICS) (H4DO (HEV))>DIAGNOSTIC TROUBLE CODE (DTC) .

    No  : Go to  3.

  3. CHECK EXPERIENCE OF RUNNING OUT OF FUEL  .

    Check if there was an experience of running out of fuel using "Check List for Interview". Ref. to ENGINE (DIAGNOSTICS) (H4DO (HEV))>CHECK LIST FOR INTERVIEW .

    Has the vehicle experienced running out of fuel?

    Yes  : Finish the diagnosis.

    NOTE: DTC may be stored by running out of fuel.

    No  : Go to  4.

  4. CHECK FUEL PRESSURE  .
    1. Turn the ignition switch to ON.
    2. Navigate to Inspection Mode for measuring Exhaust Gas. Ref. to P-HEV HYBRID POWERTRAIN CONTROL (DIAGNOSTICS)>WORK SUPPORT>OPERATION>SERVICE MODE .
      NOTE: If it is necessary to run the engine for 10 minutes or more, fasten the driver's seat belt.
    3. Start the engine.
    4. Using the Subaru Select Monitor, read the value of [Fuel Rail Pressure A] and [Commanded Fuel Rail Pressure A] when racing the engine.
      NOTE: For detailed operation procedures, refer to "Common (Diagnostics)". Ref. to COMMON (DIAG)>DATA MONITOR .

      Is the value of [Fuel Rail Pressure A] synchronized with that of [Commanded Fuel Rail Pressure A]?

      Yes  : Go to  5.

      No 

  5. CHECK OF FUEL PUMP  .
    1. Turn the ignition switch to ON. (Engine OFF)
    2. On the item [Active Test], select [Fuel Pump Relay] and perform ON/OFF drive.
      NOTE: For detailed operation procedures, refer to "Help" of application.
    3. Check for operating sound in the fuel pump according to ON/OFF switching operation.

      Does the fuel pump emit operating sound?

      Yes  : Go to  6.

      No  : Check fuel pump circuit. Ref. to ENGINE (DIAGNOSTICS) (H4DO (HEV))>DIAGNOSTICS WITH PHENOMENON>FUEL PUMP CIRCUIT .

  6. CHECK FUEL PRESSURE (LOW PRESSURE SIDE)  .
    WARNING: Place "NO OPEN FLAMES" signs near the working area.
    CAUTION:
    • Be careful not to spill fuel.
    • Before attaching/detaching a fuel pressure gauge, release the fuel pressure.

    Check the fuel pressure on low-pressure side. Ref. to MECHANICAL (H4DO (EXCEPT FOR HEV))>FUEL PRESSURE>INSPECTION .

    Is the check result OK?

    Yes  : Go to  7.

    No  : Check the fuel pump and fuel delivery line. Ref. to FUEL INJECTION (FUEL SYSTEMS) (H4DO (HEV))>FUEL PUMP>INSPECTION . Ref. to FUEL INJECTION (FUEL SYSTEMS) (H4DO (HEV))>FUEL DELIVERY AND EVAPORATION LINES>INSPECTION .

  7. CHECK FOR FUEL DELIVERY LINE LEAKAGE (HIGH PRESSURE SIDE)  .
    1. Turn the ignition switch to ON.
    2. Navigate to Inspection Mode for measuring Exhaust Gas. Ref. to P-HEV HYBRID POWERTRAIN CONTROL (DIAGNOSTICS)>WORK SUPPORT>OPERATION>SERVICE MODE .
      NOTE: If it is necessary to run the engine for 10 minutes or more, fasten the driver's seat belt.
    3. Start the engine.
    4. Using the Subaru Select Monitor, read the change in values of [Fuel Rail Pressure A] when stopping the engine.
      NOTE:
      • In order to maintain the communication with Subaru Select Monitor, turn the ignition switch to OFF, and immediately turn it to ON.
      • For detailed operation procedures, refer to "Common (Diagnostics)". Ref. to COMMON (DIAG)>DATA MONITOR .

      Does the value of [Fuel Rail Pressure A] decrease rapidly?

      Yes  : Go to  8.

      No  : Go to  9.

  8. CHECK HIGH-PRESSURE FUEL PUMP  .

    Check the high-pressure fuel pump. Ref. to FUEL INJECTION (FUEL SYSTEMS) (H4DO (HEV))>HIGH PRESSURE FUEL PUMP>INSPECTION .

    Is the check result OK?

    Yes  : Go to  9.

    No  : Replace the high-pressure fuel pump. Ref. to FUEL INJECTION (FUEL SYSTEMS) (H4DO (HEV))>HIGH PRESSURE FUEL PUMP .

  9. CHECK FOR REPRODUCTION OF FAILURE  .
    1. Using the Subaru Select Monitor or a general scan tool, perform the clear memory of [Engine]. Ref. to COMMON (DIAG)>CLEAR MEMORY .
    2. Perform the corresponding inspection mode. Ref. to ENGINE (DIAGNOSTICS) (H4DO (HEV))>INSPECTION MODE .
    3. Using the Subaru Select Monitor or a general scan tool, read the DTC of [Engine]. Ref. to COMMON (DIAG)>DIAGNOSTIC TROUBLE CODE (DTC) .

      Is DTC P0087 displayed? (Current malfunction)

      Yes  : Replace the high-pressure fuel pump. Ref. to FUEL INJECTION (FUEL SYSTEMS) (H4DO (HEV))>HIGH PRESSURE FUEL PUMP . After replacement, go to the next step. Go to  10.

      NOTE: When the high-pressure fuel pump has been replaced in step 8, go to the next step without replacing the high-pressure fuel pump. Go to  11.

      No  : End.

  10. CHECK FOR REPRODUCTION OF FAILURE  .
    1. Using the Subaru Select Monitor or a general scan tool, perform the clear memory of [Engine]. Ref. to COMMON (DIAG)>CLEAR MEMORY .
    2. Perform the corresponding inspection mode. Ref. to ENGINE (DIAGNOSTICS) (H4DO (HEV))>INSPECTION MODE .
    3. Using the Subaru Select Monitor or a general scan tool, read the DTC of [Engine]. Ref. to COMMON (DIAG)>DIAGNOSTIC TROUBLE CODE (DTC) .

      Is DTC P0087 displayed? (Current malfunction)

      Yes  : Go to  11.

      No  : End.

  11. CHECK FOR FUEL DELIVERY LINE LEAKAGE (HIGH PRESSURE SIDE)  .
    1. Turn the ignition switch to ON.
    2. Navigate to Inspection Mode for measuring Exhaust Gas. Ref. to P-HEV HYBRID POWERTRAIN CONTROL (DIAGNOSTICS)>WORK SUPPORT>OPERATION>SERVICE MODE .
      NOTE: If it is necessary to run the engine for 10 minutes or more, fasten the driver's seat belt.
    3. Start the engine.
    4. Using the Subaru Select Monitor, read the change in values of [Fuel Rail Pressure A] when stopping the engine.
      NOTE:
      • In order to maintain the communication with Subaru Select Monitor, turn the ignition switch to OFF, and immediately turn it to ON.
      • For detailed operation procedures, refer to "Common (Diagnostics)". Ref. to COMMON (DIAG)>DATA MONITOR .

      Does the value of [Fuel Rail Pressure A] decrease rapidly?

      Yes  : Replace the fuel injector. Ref. to FUEL INJECTION (FUEL SYSTEMS) (H4DO (HEV))>FUEL INJECTOR .

      No  : Repair the poor contact of ECM connector.

scientia non olet · About LEMON Manuals