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DTC P04DF

DTC P04DF  : EVAP System High Purge Flow Detected

Special Tools Required 

Vacuum Pump/Gauge, 0-30 inHg Snap-on YA4000A or equivalent, commercially available 

Vacuum/Pressure Gauge, 0-4 inHg 07JAZ-001000B 

NOTE: Before you troubleshoot, review the general troubleshooting information .
DTC Description Confirmed DTC Pending DTC
P04DF EVAP System High Purge Flow Detected    

DTC (PGM-FI)

  1. Problem verification

    -1. Turn the vehicle to the ON mode.

    -2. Clear the DTC with the HDS.

    -3. Select the EVAP TEST in the Function Test Menu, then select the FUNCTION TEST with the HDS.

    NOTE: If the test could not be completed because of another DTC, do the troubleshooting for that DTC.

    EVAP TEST

    Is the result OK?

    YES 

    Intermittent failure, the system is OK at this time. Check the EVAP canister purge valve for debris that may cause it to stick open intermittently. If the on-board snapshot of this DTC is recorded, try to reproduce the failure under the same conditions with the on-board snapshot .

    NO 

    The failure is duplicated. Go to step 2.

  2. EVAP canister purge valve open stuck check

    -1. Disconnect the vacuum hose (purge line) (A) from the EVAP canister purge valve (B) in the engine compartment, then connect a T-fitting (C), a vacuum gauge, and a vacuum pump/gauge, 0-30 inHg (D), to the vacuum hose as shown.

    GHH385137Courtesy of HONDA, U.S.A., INC.

    -2. Apply about 2 kPa (0.6 inHg, 15 mmHg) of vacuum to the EVAP canister purge valve.

    Does it hold vacuum?

    YES 

    Replace the EVAP leak check module .

    NO 

    Check the hose leakage. If the hose is OK, replace EVAP canister purge valve .