FREE REPAIR MANUALS & LABOR GUIDES 1982-2013 Vehicles
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EVAP Duty Cycle

Range (0-100%)
The scan tool indicates the [1][2]EVAP duty cycle that the VCM is commanding. The EVAP duty cycle is a pulse width modulated voltage applied to the purge valve which is displayed as a percentage. A high percentage of EVAP duty cycle would indicate near maximum canister purging.