The Engine Control Module (ECM) has determined that a malfunction exists in the electrical circuit for the vent valve/solenoid in the evaporative emission control system.
Engine Light ON (or Service Engine Soon Warning Light)
P0449 Chevrolet Description
The Engine Control Module (ECM) monitors the Evaporative Emission System (EVAP) Vent Valve/Solenoid system wiring for opens or shorts. The ECM sets the OBDII code when EVAP Vent Valve/Solenoid is not to factory specifications.