P0440 on a 2017 Nissan Altima
EVAP System Malfunction (Generic)
P0440 on a 2017 Nissan Altima indicates evap system malfunction (generic). It usually stays drivable short-term but should be diagnosed promptly. The most common cause is loose, worn, or wrong-spec fuel cap (typically $15–$60). Confirm the root cause before replacing parts.
What does P0440 mean on a 2017 Nissan Altima?
P0440 is a generic evaporative emission (EVAP) system fault. The EVAP system captures fuel vapors from the tank and routes them through the charcoal canister to be burned by the engine instead of vented into the atmosphere. P0440 is set when the ECM detects that this sealed system has lost its ability to hold pressure or vacuum during a leak test. It is almost always the first sign of a small leak somewhere between the fuel tank and the engine intake.
This guide covers P0440 across the 2015-2019 Nissan Altima generation — the symptoms, causes, and diagnostic steps below apply to every model year from 2015 through 2019.
Is it safe to drive a 2017 Nissan Altima with P0440?
In most cases a 2017 Nissan Altima stays drivable for short trips with P0440 active, but diagnose and repair it promptly. This is a low-severity code — ignoring it can lead to further damage or a failed emissions test.
What are the symptoms of P0440 on a 2017 Nissan Altima?
- Check Engine Light is illuminated
- Faint fuel smell when filling the tank or shortly after
- No drivability problem in most cases
- Fuel-cap warning light on some vehicles
- Vehicle will fail emissions / smog testing
What causes P0440 on a 2017 Nissan Altima?
| Cause | Likelihood | Estimated repair (USD) |
|---|---|---|
| Loose, worn, or wrong-spec fuel cap Always the first thing to check — costs nothing to tighten or replace. | Most common | $15–$60 |
| Cracked, kinked, or disconnected EVAP hose | Common | $30–$200 |
| Failed EVAP purge valve (purge solenoid) stuck open or closed | Common | $80–$300 |
| Failed EVAP canister vent valve / vent solenoid | Common | $80–$350 |
| Cracked or damaged EVAP charcoal canister | Occasional | $200–$600 |
| Pinhole leak in fuel filler neck or tank seam | Occasional | $150–$800 |
| Failed fuel tank pressure sensor | Occasional | $100–$350 |
How to diagnose this on a 2017 Nissan Altima
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Inspect and re-seat the fuel cap
Remove the fuel cap and check the rubber gasket for damage, debris, or twisting. Reinstall hand-tight until the cap clicks. Many vehicles require 3+ click stops. Clear the code and drive several drive cycles to allow the EVAP monitor to retest.
Tools: None
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Read mode 6 / EVAP monitor data
Pull mode 6 test results for the EVAP system. Look at the small-leak, large-leak, and purge flow test IDs. The specific test that failed narrows the diagnosis from "EVAP system" to which subsystem within it.
Tools: Scan tool with mode 6 support
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Smoke-test the EVAP system
Introduce low-pressure smoke (typically 0.5 psi) into the EVAP service port. Inspect every hose joint, the charcoal canister, the purge and vent solenoids, the filler neck, and the tank top. Smoke escaping anywhere is the leak — repair it and retest.
Tools: EVAP smoke machine, UV dye and light (optional), Inspection mirror
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Bench-test the purge valve and vent valve
Remove the purge valve and apply 12 V across its terminals. It should click and open. With no voltage, it should hold vacuum. The vent valve operates in reverse — normally open, closes when energized. Either valve stuck the wrong way will set P0440.
Tools: 12 V test source, Hand vacuum pump
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Check the fuel tank pressure sensor reading
Compare the live tank pressure PID to a known-good vehicle. A reading that does not change when the cap is removed or when the purge valve is commanded indicates either a failed sensor or a blocked hose to it.
Tools: Scan tool
NHTSA complaints & recalls for the 2017 Nissan Altima
Owner-reported safety complaints and official recalls filed with the U.S. National Highway Traffic Safety Administration for the 2017 Nissan Altima. Use these to gauge how common a problem is on your specific vehicle before you start chasing Nissan Altima diagnostics.
- POWER TRAIN 132
- VEHICLE SPEED CONTROL 39
- ENGINE 39
- AIR BAGS 69
- UNKNOWN OR OTHER 62
3 active recalls
- STRUCTURE:EMERGENCY:ESCAPE/EGRESS/EXIT Dec 2018
Nissan North America, Inc. (Nissan) is recalling certain 2015-2017 Altima vehicles, previously remedied under recall number 17V-040. The door latch-lock cable may not have been routed properly in the rear door when the remedy was applied. As a result, the cable may interfere wi…
NHTSA campaign 18V915000 - LATCHES/LOCKS/LINKAGES:DOORS:LATCH Jan 2017
Nissan North America, Inc. (Nissan) is recalling certain 2015-2017 Altima vehicles. The rear door latch/lock cable on the vehicles may have been improperly routed. As a result, lowering a rear window may inadvertently cause that door to unlatch and open.…
NHTSA campaign 17V040000 - LATCHES/LOCKS/LINKAGES:HOOD:LATCH May 2020
Nissan North America, Inc. (Nissan) is recalling certain model year 2013-2018 Nissan Altima vehicles. If the primary hood latch is inadvertently released, there is an increased likelihood that the secondary hood latch may corrode over time.…
NHTSA campaign 20V315000
How do I fix P0440 on a 2017 Nissan Altima?
- Replace the fuel cap with an OEM spec part
- Replace cracked or aged EVAP hoses
- Replace the EVAP purge valve
- Replace the EVAP vent valve / vent solenoid
- Replace the EVAP charcoal canister
About the 2015-2019 Nissan Altima
The 2015-2019 Nissan Altima was commonly sold with the following powertrains: 2.5L I4, 2.0L VC-Turbo I4, 3.5L V6. Common trims include S, SV, SR, SL, Platinum.
P0440 vs the more specific EVAP codes
P0440 is the catch-all. If the ECM can identify the type of failure more specifically, it will set a narrower code: P0442 (small leak), P0455 (large leak), P0446 (vent control), and so on. Older vehicles often set P0440 when newer vehicles would set one of the more specific codes for the same underlying condition.
Why the gas cap is always step one
A loose or damaged gas cap accounts for roughly one-third of all P0440 set events. The cap is the cheapest part to replace and the most common point of failure. Always tighten until you hear 3+ clicks, and replace any cap whose gasket shows cracks or hardening.
How long after a repair until the code clears
The EVAP leak test only runs under specific conditions: cold soak (engine off for several hours), partial fuel tank (typically 25–75 % full), and a specific outside temperature range. After a repair, expect 2–4 drive cycles before the monitor completes and the readiness flag turns “ready.” Clearing the code with a scan tool removes the light immediately, but the monitor must complete naturally before emissions testing will pass.
P0440 on a 2017 Nissan Altima: frequently asked questions
What does diagnostic trouble code P0440 mean on a 2017 Nissan Altima?
P0440 is a generic evaporative emission (EVAP) system fault. The EVAP system captures fuel vapors from the tank and routes them through the charcoal canister to be burned by the engine instead of vented into the atmosphere. P0440 is set when the ECM detects that this sealed system has lost its ability to hold pressure or vacuum during a leak test. It is almost always the first sign of a small leak somewhere between the fuel tank and the engine intake.
What are the symptoms of P0440 on a 2017 Nissan Altima?
Check Engine Light is illuminated. Faint fuel smell when filling the tank or shortly after. No drivability problem in most cases. Fuel-cap warning light on some vehicles. Vehicle will fail emissions / smog testing
What causes P0440 on a 2017 Nissan Altima?
Loose, worn, or wrong-spec fuel cap (most-common). Cracked, kinked, or disconnected EVAP hose (common). Failed EVAP purge valve (purge solenoid) stuck open or closed (common). Failed EVAP canister vent valve / vent solenoid (common). Cracked or damaged EVAP charcoal canister (occasional). Pinhole leak in fuel filler neck or tank seam (occasional). Failed fuel tank pressure sensor (occasional)
Is it safe to drive a 2017 Nissan Altima with P0440?
In most cases a 2017 Nissan Altima stays drivable for short trips with P0440 active, but it should be diagnosed and repaired promptly — this is a low-severity code. Ignoring it can lead to further damage or a failed emissions test.