Natural Vacuum Leak Detection With Purge Monitor

This monitor requires a cool down cycle, usually an overnight soak for at least 8 hours without the engine running. The ambient temperature must decrease overnight - parking the vehicle outside is advised. To run this test the fuel level must be between 15-85% full. For the monitor run conditions select the EVAP MON PRE-TEST in the SCAN TOOL, OBD II Monitors Menu.The Purge monitor will run if the small leak test reports a pass. Criteria for NVLD monitor:
- Engine off time greater than @ one hour.
- Fuel Level between 15% and 85 %.
- Start Up ECT and IAT within 10° C (18° F).
- Vehicle started and run until Purge Monitor reports a result.

NOTE: If the vehicle does not report a result and the conditions where correct. It may take up to two weeks to fail the small leak monitor. DO NOT use this test to attempt to determine a fault. Use the appropriate service information procedure for finding a small leak. If there are no faults and the conditions are correct this test will run and report a pass. Note the Small leak test can find leaks less than 10 thousands of an inch. If a small leak is present it takes approximately one week of normal driving to report a failure.