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Home >> Acura >> 2009 >> CSX Base, Automatic >> Repair and Diagnosis >> Engine Performance >> System >> EVAP System >> DTC Troubleshooting >> DTC P0497: EVAP System Low Purge Flow Detected
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DTC P0497: EVAP System Low Purge Flow Detected

Special Tools Required 

NOTE: Before you troubleshoot, record all freeze data and any on-board snapshot, and review the general troubleshooting information (see GENERAL TROUBLESHOOTING INFORMATION ).
  1. Check the fuel fill cap installation (The cap must say "TIGHTEN TO CLICK". The cap should tighten 1/4 turn after it is tight).

    Is the fuel fill cap installed and properly tightened? 

    YES  | Go to step 2.

    NO  | Properly install the fuel fill cap, then go to step  23.

  2. Turn the ignition switch ON (II).
  3. Clear the DTC with the HDS.
  4. Do the 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, the EVAP canister purge valve, or the EVAP canister vent shut valve and the ECM/PCM.

    NO  | Go to step 5.

  5. Check for a loose or damaged EVAP canister purge line between the intake manifold and the EVAP canister purge valve.

    Is the line OK? 

    YES  | Go to step 6.

    NO  | Reconnect or repair the EVAP canister purge line, then go to step  23.

  6. Disconnect the vacuum hose (A) from the EVAP canister purge valve (B) in the engine compartment, and connect a T-fitting (C) between the vacuum gauge, the vacuum pump/gauge, 01 30 in.Hg, and the vacuum hose as shown.
    Fig 1: Connecting T-Fitting Between Vacuum Gauge, Vacuum Pump And Vacuum Hose
    G06265897Courtesy of AMERICAN HONDA MOTOR CO., INC.
  7. Select EVAP PCS ON in the INSPECTION MENU with the HDS.
  8. Slowly apply about 2 kPa (15 mmHg, 0.6 in.Hg) of vacuum to the hose.

    Does it hold vacuum? 

    YES  | Replace the EVAP canister purge valve, then go to step  22.

    NO  | Go to step 9.

  9. Reconnect the vacuum hose to the EVAP canister purge valve.
  10. Disconnect the vacuum hose from the purge line (at the EVAP canister side), and connect a T-fitting (A) between the vacuum gauge and the vacuum pump/gauge, 0 | 30 in.Hg, as shown.
    Fig 2: Connecting T-Fitting Between Vacuum Gauge And Vacuum Pump
    G06265898Courtesy of AMERICAN HONDA MOTOR CO., INC.
  11. Select EVAP PCS ON in the INSPECTION MENU with the HDS.
  12. Slowly apply about 2 kPa (15 mmHg, 0.6 in.Hg) of vacuum to the hose.

    Does it hold vacuum? 

    YES  | Check for a resticted EVAP canister purge line between the EVAP canister purge valve and the EVAP canister, then go to step  22.

    NO  | Go to step 13.

  13. Remove the FTP sensor with its connector connected (see FTP SENSOR REPLACEMENT ).
  14. Connect a T-fitting (A) between the vacuum pump/ gauge, 0 | 30 in.Hg, the vacuum pump, and the FTP sensor (B) as shown.
    Fig 3: Connecting T-Fitting Between Vacuum Pump/ Gauge, Vacuum Pump And FTP Sensor
    G06265899Courtesy of AMERICAN HONDA MOTOR CO., INC.
  15. Check and record the FTP SENSOR reading in the DATA LIST with the HDS.
  16. Slowly apply about 1.3 kPa (10 mmHg, 0.4 in.Hg) of vacuum to the hose.
  17. Check the FTP SENSOR in the DATA LIST with the HDS.

    Is the difference more than 1.1 kPa (8 mmHg, 0.31 in.Hg) before and after applying vacuum? 

    YES  | Go to step 18.

    NO  | Replace the FTP sensor (see FTP SENSOR REPLACEMENT ), then go to step  22.

  18. Reconnect the vacuum hoses to the EVAP canister purge line (EVAP canister side), and reinstall the FTP sensor.
  19. Disconnect the vacuum hose (purge line) (A) from the EVAP canister purge valve (B), and connect a T-fitting (C) between the vacuum gauge and the vacuum pump/gauge, 0 | 30 in.Hg, as shown.
    Fig 4: Connecting T-Fitting Between Vacuum Gauge And Vacuum Pump
    G06265900Courtesy of AMERICAN HONDA MOTOR CO., INC.
  20. Select EVAP CVS ON in the INSPECTION MENU with the HDS.
  21. Slowly apply about 2 kPa (15 mmHg, 0.6 in.Hg) of vacuum to the hose.

    Does the hose hold vacuum? 

    YES  | Check for blockage at the EVAP canister port, then go to step 22.

    NO  | Replace the EVAP canister vent shut valve (see EVAP CANISTER VENT SHUT VALVE REPLACEMENT ), then go to step 22.

  22. Reconnect all hoses.
  23. Turn the ignition switch ON (II).
  24. Reset the ECM/PCM with the HDS.
  25. Do the ECM/PCM idle learn procedure (see ECM/PCM IDLE LEARN PROCEDURE ).
  26. 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, the EVAP canister purge valve, the EVAP canister vent shut valve, and the ECM/PCM, then go to step 1.



Special Tools Required 

NOTE: Before you troubleshoot, record all freeze data and any on-board snapshot, and review the general troubleshooting information (see GENERAL TROUBLESHOOTING INFORMATION ).
  1. Turn the ignition switch ON (II).
  2. Clear the DTC with the HDS.
  3. Do the 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.

    NO  | Go to step 4.

  4. Turn the ignition switch OFF.
  5. 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  24.

  6. Disconnect the vacuum hose (A) from the EVAP canister purge valve (B).
    Fig 1: Identifying Vacuum Hose And EVAP Canister Purge Valve
    G06265901Courtesy of AMERICAN HONDA MOTOR CO., INC.
  7. Disconnect the vacuum hose from the purge line (at the EVAP canister side), and connect a T-fitting (A) between the vacuum gauge and the vacuum pump/ gauge, 0 30 in.Hg, as shown.
  8. Apply about 2 kPa (15 mmHg, 0.6 in.Hg) of vacuum to the hose.
    Fig 2: Connecting T-Fitting Between Vacuum Gauge And Vacuum Pump
    G06265902Courtesy of AMERICAN HONDA MOTOR CO., INC.
  9. Select EVAP PCS ON in the INSPECTION MENU with the HDS.

    Does the vacuum release momentary? 

    YES  | Go to step  14.

    NO  | Go to step 10.

  10. Select EVAP PCS OFF in the INSPECTION MENU with the HDS.
  11. Disconnect the vacuum hose (A) from the EVAP canister purge valve (B). Connect a T-fitting (C) between the vacuum gauge and the vacuum pump/ gauge, 01 30 in.Hg, and the EVAP canister purge valve as shown.
    Fig 3: Connecting T-Fitting Between Vacuum Gauge And Vacuum Pump And EVAP Canister Purge Valve
    G06265903Courtesy of AMERICAN HONDA MOTOR CO., INC.
  12. Apply about 2 kPa (15 mmHg, 0.6 in.Hg) of vacuum to the hose.
  13. Select EVAP PCS ON in the INSPECTION MENU with the HDS.

    Does the vacuum release momentary? 

    YES  | Check for blockage in the vacuum hose between the EVAP canister purge valve and the EVAP canister, then go to step  24.

    NO  | Replace the EVAP canister purge valve (see EVAP CANISTER VENT SHUT VALVE REPLACEMENT ), then go to step  24.

  14. Connect the vacuum pump/gauge, 0 | 30 in.Hg, to the vacuum hose (A) as shown.
    Fig 4: Connecting Vacuum Pump To Vacuum Hose
    G06265904Courtesy of AMERICAN HONDA MOTOR CO., INC.
  15. Start the engine, and let it idle.

    Is there vacuum? 

    YES  | Go to step 16.

    NO  | Check for blockage at the EVAP purge line between the throttle body and the EVAP canister purge valve, then go to step  24.

  16. Turn the ignition switch OFF.
  17. Remove the FTP sensor with its connector connected (see FTP SENSOR REPLACEMENT ).
  18. Connect a T-fitting (A) between the vacuum pump/ gauge, 0 | 30 in.Hg and the vacuum pump, and the FTP sensor (B) as shown.
    Fig 5: Connecting T-Fitting Between Vacuum Pump And Vacuum Pump And FTP Sensor
    G06265905Courtesy of AMERICAN HONDA MOTOR CO., INC.
  19. Turn the ignition switch ON (II).
  20. Check and record the FTP SENSOR reading in the DATA LIST with the HDS.
  21. Slowly apply about 1.3 kPa (10 mmHg, 0.4 in.Hg) of vacuum to the hose.
  22. 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 23.

  23. Replace the FTP sensor (see FTP SENSOR REPLACEMENT ).
  24. Reconnect all hoses.
  25. Turn the ignition switch ON (II).
  26. Reset the ECM with the HDS.
  27. Do the ECM 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 the ECM, then go to step 1.

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