LSS V6-3.8L VIN K (1997)
Canister Purge Solenoid: Description and Operation
The EVAP purge valve allows manifold vacuum to purge the canister. The Powertrain Control Module (PCM) supplies a ground to energize the
EVAP purge valve (purge ON ). The EVAP purge valve control circuit 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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After 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, intake air temperature, and
throttle position. Canister purge will be disabled if TP angle increases to above 70%. Canister purge will be re-enabled when TP angle decreases
below 66%.