The P1446 code is a manufacturer-specific code most commonly found on Nissan and Infiniti vehicles (1998–2015 era). It means the EVAP canister vent control valve is either stuck closed (95% of cases) or has an electrical fault.
When this valve fails, the fuel tank cannot properly vent during refueling or EVAP testing → check engine light + possible refueling issues.
What Exactly Does P1446 Mean?
The EVAP system prevents fuel vapors from escaping into the atmosphere. The canister vent control valve (usually mounted near the charcoal canister above the rear axle) stays open normally and closes only during EVAP leak tests.
If the ECM commands it closed but still sees vacuum/pressure, it assumes the valve is stuck closed → P1446.
Long-tail keywords: P1446 Nissan vent control valve stuck closed fix, Infiniti G35 G37 QX56 P1446 EVAP valve replacement.
Common Symptoms of P1446
- Check Engine Light (CEL) on
- Difficulty or premature pump shut-off when refueling
- Failed emissions / smog test (EVAP monitor incomplete)
- Fuel smell in rare cases
- No drivability issues
Most Common Causes
- Faulty canister vent control valve (Nissan part #14935-AM60A/B or 14935-JF00B)
- Clogged or saturated charcoal canister
- Damaged, pinched, or disconnected vent hoses
- Water intrusion or corrosion in valve connector
- Dirt/debris blocking the valve (common in dusty areas)
Step-by-Step Diagnosis
- Scan with a tool that can perform EVAP vent valve bi-directional test
- Visually inspect valve and hoses near rear axle/fuel tank
- Apply 12V directly to valve terminals → should hear a loud click
- Command valve closed with scanner → fuel tank should hold slight vacuum
- Blow through the valve (unplugged) → should flow freely when open
Best Diagnostic Tool for P1446 in 2025: iCarsoft CR Ultra P
Generic OBD2 readers can only read the code. The iCarsoft CR Ultra P professional tablet allows:
- Bi-directional control of the EVAP vent valve on Nissan, Infiniti, Toyota, Honda, GM, Ford and 200+ brands
- Full EVAP system tests & live data graphing
- Works perfectly on Altima, Maxima, Pathfinder, Frontier, Xterra, Murano, G35, G37, FX35, QX56, Titan, Armada and all 1996–2025 models
- Topology mapping + 41+ service functions
Get iCarsoft CR Ultra P – Fix P1446 in Minutes
Typical Repair Costs
| Repair | Average Cost (Parts + Labor) |
|---|---|
| Replace vent control valve only | $120–$280 |
| Valve + charcoal canister | $450–$850 |
| Shop diagnosis + repair | $250–$650 |
Frequently Asked Questions (FAQ) – P1446
Can I drive with P1446?
Yes, no performance loss, but you’ll fail emissions and may have trouble filling the tank.
Most common vehicles that get P1446?
Nissan Altima (2002–2013), Maxima, Pathfinder, Frontier, Xterra, Sentra; Infiniti G35, G37, QX56, FX35 – especially in hot/humid climates.
Will cleaning the valve fix P1446?
Sometimes yes (blow compressed air through it), but replacement is more reliable.
Best scanner for Nissan EVAP bi-directional tests?
iCarsoft CR Ultra P – full Nissan/Infiniti enhanced diagnostics at a fraction of Consult-III price.
External resources: OBD-Codes.com P1446 | Nissan Service Bulletin NTB09-109
