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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 (DIAGNOSTICS)>DIAGNOSTIC TROUBLE CODE (DTC)

    Is DTC other than P04F0 displayed? (Current code)

    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 No. 2
      • Between check valve No. 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

    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 No. 1 and No. 2 for stuck. Ref. to EMISSION CONTROL (AUX. EMISSION CONTROL DEVICES) (H4DOTC)>CHECK VALVE

    Is the check result OK?

    Yes  : Go to  5.

    No  : Replace the check valve No. 1 or No. 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

    Is the check result OK?

    Yes  : End.

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