Vent solenoid won't close

Question

Code P0442
Solenoid will close with battery voltage
Have 14 open circuit volts at plug

Answer 1

P0442 Evaporative emission (EVAP) system small leak detected

P0442 will give small leak detected with key on engine off you will have B+ on one side of the circuit, with the vent commanded close you should have 5volt-4.5volts. this will cause the vent to close less than this voltage you will have P0449 which is vent solenoid circuit failure . The vent solenoid is normally open . You may have a small leak being detected, or even a faulty FTP (fuel tank pressure sensor) giving the wrong pressure or vacum reading