Skylark V6-3100 3.1L VIN M SFI (1996)
Canister Purge Solenoid: Description and Operation
The EVAP purge solenoid valve allows manifold vacuum to purge the canister. The Powertrain Control Module (PCM) supplies a ground to
energize the EVAP purge solenoid valve (purge ON). The EVAP purge solenoid control is Pulse Width Modulated (PWM) or turned ON and OFF
several times a second. The PCM controlled PWM output is commanded when the appropriate conditions have been met:
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Engine coolant temperature above 25°C (77°F ).
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Afier the engine has been running about 2 1/2 minutes on a cold start or 30 seconds on a warm start.
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The vehicle is operating in closed loop fuel control.
Canister purge PWM duty cycle varies according to operating conditions determined by mass air flow, fuel trim, and intake air temperature.
Canister purge will be disabled if throttle position angle increases to above 70%. Canister purge will be re-enabled when throttle position angle
decreases below 66%.
