P0440 on Nissan
Evaporative Emission Control System Malfunction
P0440 on Nissan vehicles indicates evaporative emission control system malfunction. Au7o has documented this code across 3 Nissan models — most commonly on Frontier, Quest, Sentra. This code indicates a general malfunction in the Evaporative Emission Control (EVAP) system, which captures fuel vapors from the gas tank and routes them to be burned by the engine instead of escaping into the air. The computer ran a self-test and detected the sealed vapor system isn't holding pressure or vacuum correctly, often signaling a leak somewhere in the system. The most frequent and easiest cause is a loose or faulty gas cap. The car will run normally, but it will fail an emissions test and may smell faintly of fuel. Typical repair costs on Nissan range from $100 to $1,500, depending on the specific model and root cause.
Common Causes of P0440
- •Loose, damaged, or missing gas cap
- •Cracked or disconnected EVAP hose
- •Faulty purge valve/solenoid
- •Faulty vent valve/solenoid
- •Leaking charcoal canister
- •Damaged fuel tank filler neck or seal
- •Faulty leak detection pump or pressure sensor
P0440 on Nissan by Model
Nissan Frontier(1 issue)
- EVAP Canister and Vent Control Valve Failure Triggering Check Engine Light2000-2004
The evaporative emissions system on these trucks commonly develops faults from a sticking vent control valve, saturated charcoal canister, cracked hoses, or rust/dirt intrusion near the rear-mounted canister. Owners frequently report persistent check-engine lights and failed emissions inspections even though the truck otherwise drives normally. Nissan published EVAP-related service bulletins for leak and vent valve diagnosis on Frontier/Xterra-era trucks.
Nissan Quest(1 issue)
- Rear A/C System Failure2011-2017
The Quest rear A/C system fails prematurely due to the rear evaporator developing leaks. The rear A/C then blows warm air while the front works normally. The rear expansion valve can also stick, preventing proper refrigerant flow. Repairing the rear A/C requires significant disassembly of interior panels.
Nissan Sentra(1 issue)
- Fuel Filler Neck Corrosion and Rust-Through Triggering EVAP Leaks and Fuel Smell2000-2006
In rust-belt climates, the Sentra's steel fuel filler neck commonly corrodes where road salt and debris collect behind the left rear wheel area. Owners report a strong gasoline odor after fill-ups, visible rust holes, EVAP leak codes, and in some cases fuel dripping during refueling. Nissan issued a recall on certain vehicles for corrosion of the filler tube that could lead to fuel leakage.
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View P0440 across all makes →Frequently Asked Questions
What does P0440 mean on Nissan?▼
P0440 stands for "Evaporative Emission Control System Malfunction." This code indicates a general malfunction in the Evaporative Emission Control (EVAP) system, which captures fuel vapors from the gas tank and routes them to be burned by the engine instead of escaping into the air. The computer ran a self-test and detected the sealed vapor system isn't holding pressure or vacuum correctly, often signaling a leak somewhere in the system. The most frequent and easiest cause is a loose or faulty gas cap. The car will run normally, but it will fail an emissions test and may smell faintly of fuel. On Nissan specifically, this code is documented across 3 models.
What causes P0440 on Nissan vehicles?▼
Common causes on Nissan: Loose, damaged, or missing gas cap, Cracked or disconnected EVAP hose, Faulty purge valve/solenoid, Faulty vent valve/solenoid, Leaking charcoal canister. Specific causes vary by model and year — see the per-model sections below.
How much does it cost to fix P0440 on a Nissan?▼
Repair costs on Nissan range from $100 to $1,500, depending on the specific model and root cause.
Which Nissan models have P0440 documented?▼
Au7o has documented P0440 on 3 Nissan models: Frontier, Quest, Sentra.