DTC Troubleshooting
DTC P0497: EVAP System Low Purge Flow DetectedSpecial Tools Required
- Vacuum/pressure gauge, 0-4 in.Hg 07JAZ-001000B
- Vacuum pump/gauge, 0-30 in.Hg, Snap-on YA4000A or equivalent, commercially available
NOTE: Before you troubleshoot, record all freeze data and any on-board snapshot, and review the general troubleshooting information.
1. Turn the ignition switch ON (II).
2. Clear the DTC with the HDS.
3. Select 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 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 EVAP canister.
Is the line OK?
YES - Go to step 5.
NO - Reconnect or repair the EVAP canister purge line, then go to step 26.
5. Remove the intake air duct (air flow tube).
6. Disconnect the vacuum hose (A) from the EVAP canister purge valve (B).
7. Disconnect the vacuum hose from the purge line (at the EVAP canister side), and connect a T-fitting (A) from the vacuum gauge and the vacuum pump/gauge, 0 - 30 in.Hg, to the hose as shown.
8. Apply about 2 kPa (0.6 in.Hg, 15 mmHg) of vacuum to the hose.
9. Select EVAP PCS ON in the INSPECTION MENU with the HDS.
Does the vacuum release immediately?
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) from the vacuum gauge and the vacuum pump/gauge, 0 - 30 in.Hg, to the EVAP canister purge valve as shown.
12. Apply about 2 kPa (0.6 in.Hg, 15 mmHg) of vacuum to the hose.
13. Select EVAP PCS ON in the INSPECTION MENU with the HDS.
Does the vacuum release immediately?
YES - Check for blockage in the vacuum hose between the EVAP canister purge valve and the EVAP canister, then go to step 26.
NO - Replace the EVAP canister purge valve, then go to step 26.
14. Connect the vacuum pump/gauge, 0 - 30 in.Hg, to the vacuum hose (A) as shown.
15. Reinstall the intake air duct (airflow tube). Start the engine, and let it idle.
Is there vacuum?
YES - Go to step 18.
NO - Go to step 16.
16. Turn the ignition switch OFF.
17. Inspect non-return valve A.
Is the valve OK?
YES - Check for blockage at the EVAP purge line between the throttle body and EVAP canister purge valve, then go to step 26.
NO - Replace non-return valve A, then go to step 26.
18. Turn the ignition switch OFF.
19. Remove the FTP sensor with its connector connected.
20. 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.
21. Turn the ignition switch ON (II).
22. Check and record the FTP SENSOR reading in the DATA LIST with the HDS.
23. Slowly apply about 1.3 kPa (0.4 in.Hg, 10 mmHg) of vacuum to the hose.
24. Check the FTP SENSOR in the DATA LIST with the HDS.
Does the value change?
YES - Check for debris or blockage at the FTP sensor port and at the EVAP canister, then go to step 26.
NO - Go to step 25.
25. Replace the FTP sensor.
26. Reconnect all hoses.
27. Turn the ignition switch ON (II).
28. Reset the PCM with the HDS.
29. Do the PCM idle learn procedure.
30. Select 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 PCM, then go to step 1.