P1446
EVAP Canister Vent Control Valve Closed
Get Your FREE AI Diagnostic Report
Enter your vehicle for a personalized diagnosis for code P1446
The P1446 is one of the most common Nissan-specific EVAP codes, indicating that the EVAP canister vent control valve is stuck in the closed position. This valve, located near the charcoal canister (usually underneath the vehicle near the fuel tank), allows fresh air into the EVAP canister during purge cycles. When it's stuck closed, the fuel tank can't vent properly, creating pressure buildup.
The most telltale symptom is difficulty filling your gas tank — the fuel pump nozzle keeps clicking off every few seconds as if the tank is full. You may also notice a rush of pressure when removing the gas cap. While the engine runs fine in most cases, this is an annoying problem at the pump and will cause an emissions test failure.
The fix is straightforward and relatively inexpensive. In 9 out of 10 cases, simply replacing the EVAP canister vent control valve resolves the issue. The valve is typically mounted on or near the charcoal canister underneath the vehicle and takes about 30 minutes to replace. A new valve costs $30–$100 depending on the source. Before installing the new valve, clean or replace the small filter hose that connects to it — a clogged filter is often what caused the old valve to fail in the first place.
Severity
Symptoms
- •Check engine light is on
- •Difficulty filling gas tank — pump nozzle clicks off repeatedly
- •Fuel tank feels pressurized when opening the gas cap
- •Faint gasoline odor near the vehicle
- •Vehicle may fail emissions testing
- •No significant engine performance issues
Likely Causes
Dust, dirt, or debris has jammed the spring mechanism inside the vent control valve, causing it to remain closed. The plunger inside seizes and the valve may click but won't open properly.
The small filter hose attached to the EVAP canister vent valve has become blocked with dust or debris, restricting airflow and preventing proper venting.
The charcoal canister has cracked or become waterlogged, preventing proper vapor storage and venting.
A damaged or corroded connector at the EVAP vent control valve prevents the ECM from properly commanding the valve open or closed.
Estimated Cost
Professional Repair
Includes parts + labor
Common Fixes
- Replace the EVAP canister vent control valve
- Clean or replace the vent valve filter hose
- Inspect and clean the vent valve plunger mechanism
- Check the charcoal canister for cracks or water saturation