Possible causes

– EVAP canister vent control valve
– EVAP canister is saturated with water
– EVAP control system pressure sensor and the circuit
– Blocked rubber tube to EVAP canister vent control valve
– Water separator

Tech notes

Start by checking for damage EVAP canister or hoses. If no hoses are damage the EVAP canister vent control valve may have to be replaced.

When is the code detected?

EVAP canister vent control valve remains open under specified driving conditions.

Symptoms

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

P1448 INFINITI Description

The EVAP canister vent control valve is located on the EVAP canister and is used to seal the canister vent.
This solenoid valve responds to signals from the ECM. When the ECM sends an ON signal, the coil in the solenoid valve is energized. A plunger will then move to seal the canister vent. The ability to seal the vent is necessary for the on board diagnosis of other evaporative emission control system components.
This solenoid valve is used only for diagnosis, and usually remains opened. When the vent is closed, under normal purge conditions, the evaporative emission control system is depressurized and allows EVAP Control System (Small Leak)diagnosis.

INFINITI Technical Service Bulletins for P1448 code