DTC P0497: EVAP System Low Purge Flow Detected

Special Tools Required 

• Vacuum pump/gauge, 0-30 in.Hg, Snap-on YA4000A or equivalent, commercially available
• Vacuum/pressure gauge, 0-4 in.Hg, 07JAZ-001000B

1. Turn the ignition switch ON (II).
2. Clear the DTC with the HDS.
3. Select EVAP FUNCTION TEST in the INSPECTION MENU with the HDS.

   Is the result OK? 

   YES  -Intermittent failure, the system is OK at this time. Check for poor connections or loose terminals at the FTP sensor and the ECM/PCM.

   NO  -Go to step 4.

4. Check for poor connection, blockage, or damage at the EVAP canister purge line between the throttle body and the EVAP canister.

   Is the line OK? 

   YES  -Go to step 5.

   NO  -Reconnect or repair the EVAP canister purge line, then go to step  25.

5. Disconnect the vacuum hose (A) from the EVAP canister purge valve (B).
   Fig 1: Identifying Vacuum Hose And EVAP Canister Purge Valve

   Courtesy of AMERICAN HONDA MOTOR CO., INC.
6. Disconnect the vacuum hose (A) from the purge line (at the EVAP canister side), and connect a T-fitting (B) from the vacuum gauge and the vacuum pump/gauge, 0-30 in.Hg, to the hose as shown.
   Fig 2: Disconnecting Vacuum Hose From Purge Line

   Courtesy of AMERICAN HONDA MOTOR CO., INC.
7. Apply about 2 kPa (0.6 in.Hg, 15 mmHg) of vacuum to the hose.
8. Select EVAP PCS ON in the INSPECTION MENU with the HDS.

   Does it hold vacuum? 

   YES  -Go to step 9.

   NO  -Go to step  13.

9. Select EVAP PCS OFF in the INSPECTION MENU with the HDS.
10. Disconnect the vacuum hose (A) from the EVAP canister purge valve (B). Connect a T-fitting (C) from the vacuum gauge and the vacuum pump/ gauge, 0-30 in.Hg, to the hose (D) as shown.
    Fig 3: Identifying Vacuum Hose And EVAP Canister Purge Valve

    Courtesy of AMERICAN HONDA MOTOR CO., INC.
11. Apply about 2 kPa (0.6 in.Hg, 15 mmHg) of vacuum to the hose.
12. Select EVAP PCS ON in the INSPECTION MENU with the HDS.

    Does it hold vacuum? 

    YES  -Replace the EVAP canister purge valve (see EVAP CANISTER PURGE VALVE REPLACEMENT  ), then go to step  24.

    NO  -Check for blockage in the vacuum hose between the EVAP canister purge valve and the EVAP canister, then go to step  24.

13. Connect the vacuum pump/gauge, 0-30 in.Hg, to the vacuum hose (A) as shown.
    Fig 4: Connecting Vacuum Pump/Gauge To Vacuum Hose

    Courtesy of AMERICAN HONDA MOTOR CO., INC.
14. Start the engine, and let it idle.

    Is there vacuum? 

    YES  -Go to step 15.

    NO  -Check for blockage in vacuum hose between the EVAP canister purge valve and the throttle body then go to step  24.

15. Turn the ignition switch OFF.
16. Remove the FTP sensor with its connector connected (see FTP SENSOR REPLACEMENT  ).
17. Connect a T-fitting (A) from the vacuum pump/ gauge, 0-30 in.Hg, and the vacuum pump to the FTP sensor (B) as shown.
    Fig 5: Connecting T-Fitting From Vacuum Pump/ Gauge And Vacuum Pump To FTP Sensor

    Courtesy of AMERICAN HONDA MOTOR CO., INC.
18. Turn the ignition switch ON (II).
19. Check and record the FTP SENSOR reading in the DATA LIST with the HDS.
20. Slowly apply about 1.3 kPa (0.4 in.Hg, 10 mmHg) of vacuum to the hose.
21. Check the FTP SENSOR in the DATA LIST with the HDS.

    Does the value change? 

    YES  -Check for debris or blockage at the EVAP canister port, then go to step  24.

    NO  -Go to step 22.

22. Turn the ignition switch OFF.
23. Replace the FTP sensor (see FTP SENSOR REPLACEMENT  ).
24. Reconnect all hoses.
25. Turn the ignition switch ON (II).
26. Reset the ECM/PCM with the HDS.
27. Do the ECM/PCM idle learn procedure (see ECM/PCM IDLE LEARN PROCEDURE ).
28. Do the EVAP FUNCTION TEST in the INSPECTION MENU with the HDS.

    Is the result OK? 

    YES  -Troubleshooting is complete.

    NO  -Check for poor connections or loose terminals at the FTP sensor and ECM/PCM, then go to step  1.