P1440 Nissan Code - Evaporative Emission Control System Small Leak
Quick Answer
This diagnosis detects leaks in the Evaporative Emission (EVAP) purge line using of vapor pressure in the fuel tank. Common causes include Fuel filler cap remains open or fails to close, Foreign matter caught in fuel filler cap, Incorrect fuel tank vacuum relief valve. Severity is High - diagnose this code as soon as possible. Driving is not recommended if the warning light is flashing, the engine runs poorly, or safety-related symptoms are present.
- What it means
- P1440 Nissan indicates Evaporative Emission Control System Small Leak.
- Common causes
- Common causes include Fuel filler cap remains open or fails to close, Foreign matter caught in fuel filler cap, Incorrect fuel tank vacuum relief valve.
- Severity
- High - diagnose this code as soon as possible.
- Can I drive?
- Driving is not recommended if the warning light is flashing, the engine runs poorly, or safety-related symptoms are present.
Code P1440 Nissan Description
What are the Possible Causes of the DTC P1440 Nissan?
- Fuel filler cap remains open or fails to close
- Foreign matter caught in fuel filler cap
- Incorrect fuel tank vacuum relief valve
- Incorrect fuel filler cap used
- Leak is in line between intake manifold and EVAP canister purge volume control solenoid valve
- Foreign matter caught in EVAP canister vent control valve
- EVAP canister or fuel tank leaks
- EVAP purge line (pipe and rubber tube) leaks
- EVAP purge line rubber tube bent
- Blocked or bent rubber tube to EVAP control system pressure sensor
- Loose or disconnected rubber tube
- EVAP canister vent control valve and the circuit
- O-ring of EVAP canister vent control valve is missing or damaged
- EVAP canister is saturated with water
- EVAP control system pressure sensor
- Absolute pressure sensor
How to Fix the DTC P1440 Nissan?
Review the 'Possible Causes' above and visually examine the corresponding wiring harness and connectors. Check for damaged components and inspect connector pins for signs of being broken, bent, pushed out, or corroded.
Code Tech Notes
There is a factory Nissan service bulletin to help diagnose the P1440 code:
Nissan Factory Service Bulletin OBDII Code P1440
What is the Cost to Diagnose the Code?
Labor: 1.0
To diagnose the P1440 Nissan code, it typically requires 1.0 hour of labor. Rates vary by location, vehicle, and shop. Many shops charge between $80–$150 per hour; dealerships and metro areas may be higher, independents may be lower.
Need more information about the P1440 Nissan code?
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Need Help with the Code?
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Frequently Asked Questions about P1440 Nissan Code
No Frequently Asked Questions about P1440 Nissan Code found.
Discuss the causes and fixes for P1440 Nissan OBDII Code
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No I didn't replace parts yet because I don't know what I can replace first. I re tighten the gas cap but the check engine light still come on after an hour drive.
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Small EVAP leaks are very difficult to find. If the gas cap is tight then you may have to have a repair shop find the small leak with a smog machine.
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