DTC Troubleshooting
DTC Troubleshooting: P0497
DTC P0497: EVAP System Low Purge Flow Detected
Special 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. Initial Inspection and Diagnostic Overview
1. Turn the ignition switch to 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. Turn the ignition switch to LOCK (0).
5. Check for a loose, clogged, or damaged EVAP canister purge line between the throttle body and the EVAP canister.
Is the line OK?
YES - Go to step 5.
NO - Repair or replace the EVAP canister purge line, then go to step 23.
6. Disconnect the vacuum hose (A) from the EVAP canister purge valve (B).
7. Disconnect the vacuum hose from the EVAP canister purge line (EVAP canister side), then 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 (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 15.
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 pump/gauge, 0-30 in.Hg, the vacuum pump, and the EVAP canister purge valve as shown.
12. Apply about 2 kPa (0.6 in.Hg, 15 mmHg) of vacuum to the hose.
13. Turn the ignition switch to ON (II).
14. Select EVAP PCS ON in the INSPECTION MENU with the HDS.
Does the vacuum release immediately?
YES - Check for a 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, Service and Repair then go to step 24.
15. Connect the vacuum pump/gauge, 0-30 in.Hg, to the vacuum hose (A) as shown.
16. Start the engine, and let it idle.
Is there vacuum?
YES - Go to step 17.
NO - Check for a blockage in the vacuum hose between the EVAP canister purge valve and the throttle body, then go to step 24.
17. Turn the ignition switch to LOCK (0).
18. Remove the FTP sensor with its connector connected. Service and Repair
19. Connect a T-fitting (A) between the vacuum pump/gauge, 0-30 in.Hg, the vacuum pump, and the FTP sensor (B) as shown.
20. Check and record the FTP SENSOR reading in the DATA LIST with the HDS.
21. Slowly apply about 1.3 kPa (0.4 in.Hg, 10 mmHg) 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 a blockage at the EVAP canister port, then go to step 24.
NO - Go to step 23.
23. Replace the FTP sensor. Service and Repair
24. Reconnect all hoses.
25. Turn the ignition switch to ON (II).
26. Reset the ECM/PCM with the HDS.
27. Do the ECM/PCM idle learn procedure. 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/PCM, then go to step 1.