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DTC P04AE: EVAP System Purge Control Valve "B" Performance/Stuck Open: Notes

  1. - 

    DTC detecting condition: 

    Detected when two consecutive driving cycles with fault occur.

    Trouble symptom: 

    • Improper idling
    • 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 FUEL FILLER CAP  .
    1. Turn the ignition switch to OFF.
    2. Check the fuel filler cap.
      NOTE: The DTC is stored in memory if fuel filler cap is or was loose or if the cap chain has caught while tightening.

    Is the fuel filler cap tightened securely?

    Yes  : Go to  2.

    No  : Tighten fuel filler cap securely.

  2. CHECK FUEL FILLER CAP  .

    Check the fuel filler cap.

    Is the fuel filler cap genuine?

    Yes  : Go to  3.

    No  : Replace with a genuine fuel filler cap.

  3. CHECK FUEL FILLER PIPE GASKET  .

    Check the fuel filler pipe gasket.

    Is there any damage to the seal between fuel filler cap and fuel filler pipe?

    Yes  : Repair or replace the fuel filler cap and fuel filler pipe. Ref. to FUEL INJECTION (FUEL SYSTEMS) (H4DOTC)>FUEL FILLER PIPE .

    No  : Go to  4.

  4. CHECK CHECK VALVE 1 AND 2  .

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

    Is the check result OK?

    Yes  : Go to  5.

    No  : Replace the defective check valve. Ref. to EMISSION CONTROL (AUX. EMISSION CONTROL DEVICES) (H4DOTC)>Check Valve>REMOVAL .

  5. CHECK PIPES  .

    Check that there is no dislocation and damage in the pipes between purge control solenoid valve and check valve 1 and between purge control solenoid valve and check valve 2. Ref. to FUEL INJECTION (FUEL SYSTEMS) (H4DOTC)>General Description>COMPONENT .

    Is the check result OK?

    Yes  : Go to  6.

    No  : Repair or replace faulty parts. Ref. to EMISSION CONTROL (AUX. EMISSION CONTROL DEVICES) (H4DOTC)>Check Valve>REMOVAL .

  6. CHECK PURGE CONTROL SOLENOID VALVE  .

    Check air-tightness of the purge control solenoid valve. Ref. to EMISSION CONTROL (AUX. EMISSION CONTROL DEVICES) (H4DOTC)>Purge Control Solenoid Valve>INSPECTION .

    Is the check result OK?

    Yes  : Go to  7.

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

  7. CHECK EVAPORATIVE EMISSION CONTROL SYSTEM LINE  .

    Check the evaporative emission control system line. Ref. to FUEL INJECTION (FUEL SYSTEMS) (H4DOTC)>FUEL DELIVERY AND EVAPORATION LINES .

    Are there holes on the evaporation line?

    Yes  : Repair or replace the evaporation line. Ref. to FUEL INJECTION (FUEL SYSTEMS) (H4DOTC)>FUEL DELIVERY AND EVAPORATION LINES .

    No  : Go to  8.

  8. CHECK CANISTER  .

    Check the canister. Ref. to EMISSION CONTROL (AUX. EMISSION CONTROL DEVICES) (H4DOTC)>Canister>INSPECTION .

    Are there holes on the canister?

    Yes  : Replace the canister. Ref. to EMISSION CONTROL (AUX. EMISSION CONTROL DEVICES) (H4DOTC)>CANISTER .

    No  : Go to  9.

  9. CHECK LEAK CHECK VALVE ASSEMBLY  .

    Check the leak check valve assembly. Ref. to EMISSION CONTROL (AUX. EMISSION CONTROL DEVICES) (H4DOTC)>Leak Check Valve Assembly>INSPECTION .

    Are there damage or holes on the leak check valve assembly?

    Yes  : Replace the leak check valve assembly. Ref. to EMISSION CONTROL (AUX. EMISSION CONTROL DEVICES) (H4DOTC)>Leak Check Valve Assembly>REMOVAL .

    No  : Go to  10.

  10. CHECK FUEL TANK  .
    WARNING: Place "NO OPEN FLAMES" signs near the working area.

    Remove the fuel tank. Ref. to FUEL INJECTION (FUEL SYSTEMS) (H4DOTC)>FUEL TANK .

    Are there damage or holes on the fuel tank?

    Yes  : Repair or replace the fuel tank. Ref. to FUEL INJECTION (FUEL SYSTEMS) (H4DOTC)>FUEL TANK .

    No  : Go to  11.

  11. CHECK STATUS OF EVAPORATIVE EMISSION CONTROL SYSTEM  .

    Check the condition of evaporative emission control system for other mechanical defects.

    Are there holes, cracks, clogging, or disconnection, misconnection of hoses or pipes in evaporative emission control system?

    Yes  : Repair or replace the hoses or pipes.

    No  : Repair the poor contact of ECM connector.

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