P0455 on 2015-2022 Nissan Altima: EVAP Large Leak Causes and Fixes

What's Unique About the 2015-2022 Nissan ALTIMA

While P0455 is a universal code, Nissan Altimas from this era, along with many other Nissan models like the Rogue and Sentra, are particularly known for issues with the EVAP canister vent control valve. This component, located near the rear of the car by the charcoal canister, is exposed to road debris and moisture, causing it to fail and stick open, which directly causes a large leak code. Nissan has issued several versions of Technical Service Bulletin NTB13-097, which covers P0455 and related EVAP codes, providing a specific diagnostic flowchart for technicians and indicating this is a well-documented issue for the brand. 🎬 Watch: Overview of Nissan P0455 causes and common fixes The first step is always the gas cap, but on these cars, the vent valve should be the next primary suspect.

Diagnostic Flowchart

Tap your situation to follow the diagnostic path that matches what you're seeing on this vehicle.

Generation note: The 2015-2022 range covers two Altima generations: the 5th (L33, 2013-2018) and 6th (L34, 2019-Present). The causes and diagnostic principles for P0455 are the same for both. However, the exact location and part numbers for components like the purge valve and vent control valve may differ. For example, the purge valve for the L34 Altima with the 2.0L engine is a different part from the L33 models. The vent control valve has had several part number revisions, with 14935-JF02C being a common replacement for many models in this date range. Always verify the correct part for your specific model year and VIN with a dealer or reliable parts catalog, as mid-year production changes can occur.

Symptoms You May Notice

• Check Engine Light is on
• A faint to strong smell of fuel, particularly around the rear of the car or after refueling
• A "Loose Fuel Cap" message may appear on the dashboard display
• In some related cases, difficulty filling the gas tank (the pump nozzle clicks off repeatedly) can indicate a vent valve that is stuck closed, which is the opposite problem but involves the same part.

Most Likely Causes

1. Loose or Faulty Gas Cap 🔴 High Probability This is the most common cause on any vehicle. The gas cap seal can degrade over time or simply not be tightened correctly after refueling, triggering a "gross leak" code.
   How to confirm: Remove the gas cap and inspect the rubber O-ring for cracks, dirt, or stiffness. Ensure the cap is tightened until it clicks at least once. If the seal is damaged, replace the cap.
   Typical fix: Tighten or replace the gas cap. It is highly recommended to use a genuine OEM Nissan cap, as some aftermarket caps do not seal properly and can cause the code to return. After replacing, the code may take several drive cycles to clear.
   Est. part cost: $25-$55
2. Faulty EVAP Canister Vent Control Valve 🔴 High Probability This is a very common failure point on Nissans. The valve is located near the charcoal canister in the rear of the car, where it is exposed to road debris and moisture, causing it to stick open and create a large leak.
   How to confirm: The valve is normally open. A mechanic can command it closed with a scan tool while performing a smoke test; if smoke escapes from the valve, it has failed. A DIY test involves removing the valve, applying 12V power to its terminals, and listening for an audible click as it closes. If it doesn't click or is stuck, it needs replacement. The valve can be removed from the canister by pushing a small tab and twisting counter-clockwise. 🎬 See this walkthrough for replacing the vent control valve
   Typical fix: Replace the EVAP canister vent control valve and its O-ring. The part is typically mounted directly to the charcoal canister and can be replaced separately. Applying a small amount of dielectric grease to the new O-ring can help with installation.
   Est. part cost: $60-$120
3. Faulty EVAP Purge Valve (Purge Solenoid) 🟡 Medium Probability Located in the engine bay, this valve can get stuck open, creating a constant vacuum leak into the EVAP system. While less common than the rear vent valve, it is still a known failure point.
   How to confirm: This valve is normally closed. Remove the valve and try to blow through it. If air passes through, it is stuck open and needs to be replaced. A scan tool can also be used to command the valve open and closed to check its function.
   Typical fix: Replace the purge valve. It is usually mounted on or near the engine's intake manifold, with two hoses and an electrical connector. 🎬 Watch: How to replace the purge solenoid on newer models
   Est. part cost: $50-$200
4. Cracked or Disconnected EVAP Hose ⚪ Low Probability Rubber hoses can become brittle and crack with age and exposure to heat cycles, especially at connection points to valves and the canister.
   How to confirm: A smoke test is the most effective way to find a leak in an EVAP line. Smoke is injected into the system's service port, and it will visibly escape from any cracks or loose connections, which can be hard to spot with a visual inspection alone.
   Typical fix: Replace the damaged section of hose and secure it with new clamps.
   Est. part cost: $10-$40

Rare But Worth Checking

• Cracked Charcoal Canister: The canister itself can be damaged by road debris or internal saturation, causing a large crack. This is less common than a valve failure but should be visually inspected, especially if a smoke test shows a leak from the canister body itself.
• Leaking Fuel Filler Neck: Rust or corrosion on the metal tube leading to the gas tank can create a leak, preventing the gas cap from sealing properly. This is more common in regions that use road salt and can be a tricky leak to find without a smoke test.
• Faulty Fuel Tank Pressure Sensor: If the sensor that reports pressure to the computer fails, it can send incorrect data, making the computer think there is a leak when there isn't one. This will usually be accompanied by other pressure sensor-specific codes.

Diagnosis Steps

1. Check the Gas Cap: Ensure it is tight and clicks. Remove it and inspect the rubber seal for any cracks or damage. A faulty cap is the most common cause. If in doubt, replace it with an OEM part.
2. Visual Inspection: Look over the EVAP hoses in the engine bay and around the canister in the rear for any obvious cracks, disconnections, or damage.
3. Test the Vent Control Valve: This is the most likely component failure on a Nissan. Locate the valve on the charcoal canister at the rear of the car. Use a scan tool to command it closed during a smoke test. If smoke still comes out of the valve, it is faulty. Alternatively, remove it, apply 12V, and listen for a click. No click means it's dead.
4. Perform a Smoke Test: This is the most reliable method for finding leaks. A smoke machine is connected to the EVAP service port in the engine bay. The system is filled with smoke, which will pour out of any leak, making it easy to pinpoint the source, be it a hose, the filler neck, or the canister itself.
5. Test the Purge Valve: Locate the purge valve in the engine bay. Disconnect it and try to blow through it. If air passes, it is stuck open and needs replacement.
6. Inspect the Charcoal Canister and Filler Neck: If the smoke test reveals a leak from the body of the canister or around the fuel filler neck, inspect these components for cracks or rust.

Parts You'll Likely Need

• Gas Cap (OEM #17251-1VZ0D (example, verify by VIN)) — This is the simplest and most frequent cause. An old, worn seal will not hold pressure. Using a non-OEM cap is a common cause of repeat codes.
  Trusted brands: Nissan (OEM)
  OEM price range: $25-$55
  Aftermarket price range: $15-$30
• EVAP Canister Vent Control Valve (OEM #14935-JF02C (supersedes 14935-JF00A, B, C, D, E)) — A very common failure item on Nissans that gets stuck open, causing a large leak. This part number has been superseded multiple times, indicating revisions to the design.
  Trusted brands: Nissan (OEM), Dorman (911-502), Hitachi
  OEM price range: $60-$120
  Aftermarket price range: $40-$80

Related Codes That Often Appear With This One

• P0442 — This code is for a 'small' EVAP leak. It can appear alongside P0455 if the system has multiple leaks of different sizes or if a failing component is creating an intermittent leak.
• P0456 — This code is for a 'very small' EVAP leak. All three codes (P0455, P0442, P0456) are addressed in the same Nissan TSBs (like NTB13-097J), as they point to the same system and often share common causes like the gas cap or vent valve.

Technical Service Bulletins (TSBs) & Recalls

• NTB13-097J
• NTB13-097G
• NTB13-097D

Platform-Specific Known Issues

• Nissan TSB NTB13-097J: Nissan has issued multiple versions of Technical Service Bulletin NTB13-097 (e.g., D, G, J) which applies to all 2012 and newer Nissan vehicles for EVAP codes P0442, P0455, and P0456. The TSB doesn't pinpoint a single part but provides a detailed diagnostic flowchart for technicians. It emphasizes first checking the gas cap and informing the customer on proper installation. It then guides the technician through using a CONSULT scan tool and a smoke machine to systematically test the system, including commanding the vent valve closed to isolate leaks. This bulletin confirms that this is a widespread and well-understood issue across the Nissan lineup.

Mechanic-Grade Diagnostic Values

• EVAP Canister Vent Control Valve Solenoid Resistance — expected: 20 - 50 Ohms. Failure: An open circuit (infinite resistance) or a reading far outside the expected range indicates a bad internal coil.
• EVAP Purge Valve Solenoid Resistance — expected: Approximately 20 Ohms. Failure: A reading significantly different from 20 Ohms suggests a faulty solenoid coil.
• Voltage at EVAP Canister Vent Control Valve Connector — expected: 12V on one wire with key in 'ON' position (engine off). Failure: No voltage indicates a problem in the power supply circuit to the valve.

Scan Tool Commands That Help

• Nissan CONSULT-III plus (or equivalent bidirectional scanner): EVAP SYSTEM CLOSE — This command, found under 'WORK SUPPORT', manually closes the normally-open vent valve. This is a required step before performing a smoke or pressure test to seal the system for an accurate leak diagnosis, as outlined in Nissan TSBs.
• Bidirectional Scan Tool: Purge Valve Duty Cycle Control — This allows a technician to command the normally-closed purge valve to open and close while the engine is off. It's used to verify the valve is not stuck and is responding to computer commands.

Wiring & Ground Locations

• EVAP Canister Vent Control Valve Wiring — At the electrical connector for the vent control valve, located on or near the charcoal canister at the rear of the vehicle.. The valve is controlled via a two-wire circuit. One wire should have a constant 12V supply whenever the ignition is on. The other wire is the ground, which is switched on and off by the Engine Control Module (ECM) to close the valve. Testing for 12V power is a key step in determining if a non-responsive valve is due to a bad valve itself or a wiring issue.

Real Owner Repair Stories

• YouTube user comment (Nissan (model not specified, but common issue)) — P0455 code
  ❌ Tried (didn't work) Replacing EVAP solenoids
  ✅ What actually fixed it The final cause was a rusted fuel filler neck that was leaking. This is a common issue in areas with road salt.
• Car Talk Community forum user (Older Nissan) — P0455 code, CEL would come on, go out, and return.
  ❌ Tried (didn't work) Using a Stant aftermarket gas cap did not resolve the issue.
  ✅ What actually fixed it The user was advised that using a genuine OEM gas cap is often necessary as some aftermarket caps do not seal correctly. The story highlights that even after a fix, the code may take many miles and several drive cycles to clear.
• YouTube video diagnosis (2008 Nissan Altima) — P0455 code
  ❌ Tried (didn't work) Testing the vent valve and purge valve showed they were functional.
  ✅ What actually fixed it A smoke test revealed a crack in a plastic hose near the fuel tank. The mechanic repaired the crack with JB Weld as a temporary, low-cost fix for the owner.

"I Checked Everything" — The Actual Cause

• In some cases, a smoke test may not reveal a leak if the technician doesn't specifically check the fuel filler neck area. A rusted-through filler neck is a known cause of P0455 on vehicles in salt-belt regions, but can be missed if the focus is only on the canister and its associated hoses.
• The code could be triggered by a faulty Fuel Tank Pressure (FTP) sensor. If the sensor provides incorrect readings to the computer, the system may log a P0455 code even if no physical leak exists. In this scenario, a smoke test would come back clean, and the sensor itself would need to be tested.

OEM Part Supersession History

• 14935-JF00A, 14935-JF00B, 14935-JF00C, 14935-JF00D, 14935-JF00E → 14935-JF02C — Nissan has revised the EVAP Canister Vent Control Valve multiple times to improve durability and prevent sticking, which is the common failure mode.
  Heads up: While older versions may fit, installing the latest revision (14935-JF02C) is highly recommended for a long-term fix. Aftermarket alternatives like the Dorman 911-502 exist, but some owners report repeat failures, making the genuine Nissan part a safer bet.

Model Year Variations Within This Range

• 2019-2022 (L34 Generation): The EVAP purge valve located in the engine bay may have a different part number and design, especially for the 2.0L (KR20DDET) engine, compared to the 2.5L engine used in both L33 and L34 generations. The fundamental diagnostic process from TSB NTB13-097J remains the same for all models.