DTC Troubleshooting
DTC Troubleshooting: P0497
DTC P0497: EVAP System Low Purge Flow Detected ('07-09 models)
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. 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 to LOCK (0).
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 6.
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).
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 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) from the vacuum gauge and the vacuum pump/gauge, 0-30 in.Hg, 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 momentary?
YES - Check for blockage in the EVAP canister purge line between the EVAP canister purge valve and the EVAP canister, then go to step 25.
NO - Replace the EVAP canister purge valve, Service and Repair then go to step 25.
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 blockage at the EVAP purge line between the throttle body and the EVAP canister purge valve, then go to step 25.
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) from the vacuum pump/gauge, 0-30 in.Hg, and the vacuum pump, to the FTP sensor (B) as shown.
20. Turn the ignition switch to ON (II).
21. Check and record the FTP SENSOR reading in the DATA LIST with the HDS.
22. Slowly apply about 1.3 kPa (0.4 in.Hg, 10 mmHg) of vacuum to the hose.
23. 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 25.
NO - Go to step 24.
24. Replace the FTP sensor. Service and Repair
25. Reconnect all hoses.
26. Turn the ignition switch to ON (II).
27. Reset the ECM with the HDS.
28. Do the ECM idle learn procedure. ECM Idle Learn Procedure
29. 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.