engine service light code says purge or vent or solenoid failure plugged canist on 2007 Cadillac CTS

failed evap pressure sensor

Asked by for the 2007 Cadillac CTS
i have 2006 cadillac cts my car is in shop for this now, it could have been gas cap, dealership says mine is purge dolenoid, charging me $95 to repair, hope this helped.