Canister purge control solenoid is controlled by the PCM. Current is supplied to solenoid when ignition is on. Solenoid is energized when PCM provides a ground circuit for solenoid. Solenoid may be normally closed or normally open. When solenoid is open, charcoal canister is purged using manifold or ported vacuum. When solenoid is closed, purge vacuum to canister is blocked.
The PCM will allow vacuum to pass through solenoid when engine has been running for more than one minute, engine is at normal operating temperature, vehicle speed is greater than a specified value and throttle is off idle. This solenoid (if used) is located in the purge line between charcoal canister and vacuum purge port, or on top of canister.