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DTC P04F0: EVAP System High Pressure Purge Line (CPC2) Performance: Notes

  1. - 

    DTC detecting condition: 

    Detected when two consecutive driving cycles with fault occur.

    Trouble symptom: 

    Fuel odor

    NOTE: After the faulty parts are repaired or replaced, perform the final check in Basic Diagnostic Procedure. Ref. to ENGINE (DIAGNOSTICS) (H4DOTC)>Basic Diagnostic Procedure>PROCEDURE .
  1. CHECK DTC  .
    1. Turn the ignition switch to ON.
    2. 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 P04F0 displayed? (Current malfunction)

    Yes  : Check the appropriate DTC using the "Diagnostic Trouble Code (DTC)". Ref. to ENGINE (DIAGNOSTICS) (H4DOTC)>Diagnostic Trouble Code (DTC)>LIST .

    No  : Go to  2.

  2. CHECK PIPES  .
    1. Turn the ignition switch to OFF.
    2. Check for disconnection or damage in the following pipes. Ref. to FUEL INJECTION (FUEL SYSTEMS) (H4DOTC)>General Description>COMPONENT .
      • Between leak check valve assembly and purge control solenoid valve
      • Between purge control solenoid valve and check valve 2
      • Between check valve 2 and intake duct No. 1

    Is the check result OK?

    Yes  : Go to  3.

    No  : Repair or replace faulty parts. Ref. to EMISSION CONTROL (AUX. EMISSION CONTROL DEVICES) (H4DOTC)>LEAK CHECK VALVE ASSEMBLY . Ref. to EMISSION CONTROL (AUX. EMISSION CONTROL DEVICES) (H4DOTC)>CHECK VALVE .

  3. CHECK PURGE CONTROL SOLENOID VALVE  .

    Check that the purge control solenoid valve has no open or close stuck. Ref. to EMISSION CONTROL (AUX. EMISSION CONTROL DEVICES) (H4DOTC)>Purge Control Solenoid Valve>INSPECTION .

    Is the check result OK?

    Yes  : Go to  4.

    No  : Replace the purge control solenoid valve. Ref. to EMISSION CONTROL (AUX. EMISSION CONTROL DEVICES) (H4DOTC)>PURGE CONTROL SOLENOID VALVE .

  4. CHECK CHECK VALVE  .

    Check the check valves 1 and 2 for stuck. Ref. to EMISSION CONTROL (AUX. EMISSION CONTROL DEVICES) (H4DOTC)>Check Valve>INSPECTION .

    Is the check result OK?

    Yes  : Go to  5.

    No  : Replace the check valve 1 or 2. Ref. to EMISSION CONTROL (AUX. EMISSION CONTROL DEVICES) (H4DOTC)>CHECK VALVE .

  5. CHECK CPC PRESSURE SENSOR  .

    Check the CPC pressure sensor. Ref. to EMISSION CONTROL (AUX. EMISSION CONTROL DEVICES) (H4DOTC)>CPC Pressure Sensor>INSPECTION .

    Is the check result OK?

    Yes  : Go to  6.

    No  : Replace the CPC pressure sensor. Ref. to EMISSION CONTROL (AUX. EMISSION CONTROL DEVICES) (H4DOTC)>CPC PRESSURE SENSOR .

  6. CHECK EJECTOR  .

    Check the ejector mechanism of the intake duct No. 1 for clogging and breakage. Ref. to INTAKE (INDUCTION) (H4DOTC)>Intake Duct>INSPECTION .

    Is the check result OK?

    Yes  : End.

    No  : Replace the intake duct No. 1 with ejector. Ref. to INTAKE (INDUCTION) (H4DOTC)>INTAKE DUCT .

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