Possible causes

– Loose or missing gas cap
– Faulty gas cap
– Canister Vent Solenoid harness is open or shorted
– Canister Vent Solenoid electrical circuit poor connection
– Faulty Canister Vent Solenoid

Symptoms

– Engine Light ON (or Service Engine Soon Warning Light)

P1451 MERCURY Description

The Engine Control Module (ECM) detected the canister vent solenoid signal moved outside the calibrated parameters at a specific duty cycle.