P0442 on 2017-2022 Nissan Murano: EVAP Small Leak Causes and Fixes

What's Unique About the 2017-2022 Nissan MURANO

On many Nissan vehicles from this era, including the Murano, the EVAP system components are a known common failure point. Nissan has issued multiple Technical Service Bulletins (TSBs) for a wide range of models regarding EVAP leak codes like P0442, P0455, and P0456. This often points to a pattern of issues with parts like the EVAP canister vent control valve, which can get stuck or fail due to dirt, moisture, and age, making it a more common culprit on these vehicles than on some other brands. The filler neck is also prone to rust, which can compromise the gas cap seal.

Diagnostic Flowchart

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

Symptoms You May Notice

• Check Engine Light is on
• A faint fuel smell near the gas tank area (less common with a small leak)
• Difficulty starting the vehicle immediately after refueling (can point to a stuck purge valve)
• A "Loose Fuel Cap" warning on the dashboard.

Most Likely Causes

1. Loose or Faulty Gas Cap 🔴 High Probability The gas cap seal is a simple rubber O-ring that can crack, get dirty, or wear out over time, preventing a proper seal. This is the most common cause for P0442 on any vehicle and is the first thing addressed by Nissan's own diagnostic procedures in TSBs like NTB13-097J.
   How to confirm: Remove the cap and inspect the rubber seal for any cracks, dirt, or stiffness. Ensure you hear a click when tightening it. Also, inspect the fuel filler neck for rust or debris that could prevent a good seal.
   Typical fix: First, try cleaning the cap's seal and the fuel filler neck. If the seal is damaged or the cap is old, replace it. It is highly recommended to use an OEM (Original Equipment Manufacturer) cap from Nissan, as aftermarket caps are notorious for causing sealing issues and repeat codes.
   Est. part cost: $20-$50
2. Faulty EVAP Canister Vent Control Valve/Solenoid 🟡 Medium Probability This valve is located near the charcoal canister under the vehicle and is exposed to road debris and moisture. It can get stuck open or closed due to dirt or internal failure, causing a leak code. This is a well-documented and very common issue on many Nissan models.
   How to confirm: The valve can be tested with a capable scan tool to see if it actuates. It can also be removed and tested by applying 12V power; you should hear a click, and the valve should close, preventing air from passing through. Often, owners will simply replace this part after the gas cap due to its high failure rate.
   Typical fix: Replacement of the vent control valve. It is typically mounted on or near the charcoal canister at the rear of the vehicle. Some owners have had success temporarily by cleaning the valve and its filter.
   Est. part cost: $50-$100
3. Faulty EVAP Canister Purge Volume Control Valve/Solenoid 🟡 Medium Probability This valve is located in the engine bay and controls the flow of fuel vapors to the engine. It can get stuck open or fail internally, creating a leak in the system. A common symptom of a stuck-open purge valve is difficulty starting the car after refueling.
   How to confirm: With the engine off, the valve should be closed. It can be tested by removing it and trying to blow through it; no air should pass. If air passes, the valve is stuck open and needs replacement. A scan tool can also command it to open and close.
   Typical fix: Replacement of the purge valve. This is usually an easy-to-access part on top of the engine, with two hoses and an electrical connector.
   Est. part cost: $40-$90
4. Cracked or Disconnected EVAP Hose ⚪ Low Probability Rubber hoses, especially the small vacuum lines in the engine bay, become brittle with age and exposure to heat and can develop small cracks that are difficult to see.
   How to confirm: A visual inspection may reveal an obvious crack or disconnected line, particularly around the purge valve. However, the most effective method is a smoke test, which forces smoke into the EVAP system to reveal the exact location of any leaks.
   Typical fix: Replace the damaged section of hose or reconnect it securely.
   Est. part cost: $10-$30

Rare But Worth Checking

• Cracked Charcoal Canister: The plastic housing of the canister can be damaged by road debris, leading to a crack and a leak. This is less common than valve failure but should be inspected, especially if you live in an area with poor road conditions.
• Leaking Fuel Tank Filler Neck: The metal pipe leading to the gas tank can rust and develop pinhole leaks over time, particularly in regions where road salt is used. This corrosion can also prevent the gas cap from sealing properly.
• Leaking Fuel Tank or Fuel Pump Gasket: The fuel tank itself or the gasket for the fuel pump assembly can develop leaks, though this is less common for a P0442 code.

Diagnosis Steps

1. Read the code with an OBD-II scanner to confirm P0442 is present.
2. Inspect the gas cap. Remove it, check the seal for cracks or debris, and clean it. Also clean the filler neck surface. Reinstall it until it clicks at least once. Clear the code and drive for a few days to see if it returns.
3. If the light returns, consider replacing the gas cap with a genuine OEM Nissan part as the next cheapest and easiest step.
4. If the code persists, perform a thorough visual inspection of all accessible EVAP hoses in the engine bay and under the vehicle, looking for obvious cracks or disconnections. Pay close attention to the small vacuum lines near the purge valve.
5. Locate the EVAP canister purge valve in the engine bay. With the engine off, remove the valve and try to blow through it. If air passes, it's faulty and needs replacement.
6. Locate the EVAP vent control valve near the charcoal canister at the rear of the vehicle. Inspect it and its filter for dirt or damage. Test it by applying 12V power to see if it clicks.
7. If the cause is still not found, the most definitive diagnostic step is to have a professional perform a smoke test. This test fills the EVAP system with a harmless, visible smoke, and any leak will be quickly identified by seeing where the smoke escapes.

Parts You'll Likely Need

• Fuel Filler Cap (OEM #17251-1LA0A) — This is the most frequent cause of a P0442 code due to its seal wearing out over time. Always start here. Using an OEM cap is critical.
  Trusted brands: Nissan (OEM)
  OEM price range: $25-$40
  Aftermarket price range: $15-$25
• Vapor Canister Vent Control Valve (OEM #14935-JF02C) — A very common failure point on Nissan vehicles. It gets stuck due to dirt and age, causing a persistent leak code even after replacing the gas cap. This part number supersedes several previous versions (14935-JF00A, 14935-JF00B, etc.).
  Trusted brands: Nissan (OEM), Bosch, Dorman, Hitachi
  OEM price range: $60-$90
  Aftermarket price range: $40-$80
• Vapor Canister Purge Valve (OEM #14930-JA10A) — Located in the engine bay, this valve can fail and stick open, causing a constant small leak. It can also cause hard starting after refueling.
  Trusted brands: Nissan (OEM), Denso, Dorman, Standard Motor Products
  OEM price range: $60-$100
  Aftermarket price range: $30-$60

Related Codes That Often Appear With This One

• P0455 — Indicates a large EVAP leak. A component that is failing intermittently, like a vent valve, might sometimes cause a small leak (P0442) and other times a large one (P0455).
• P0456 — Indicates a very small EVAP leak. This code is closely related and points to the same set of potential failures, just a different leak size threshold.

Technical Service Bulletins (TSBs) & Recalls

• NTB13-097J: EVAP LEAK DTC P0442, P0455, P0456 INFORMATION
• NTB17-082E: DTC P0456 CAUSED BY EVAP LEAK AT VENT CONTROL VALVE O-RING

Platform-Specific Known Issues

• Nissan TSB NTB13-097J: Nissan has issued a broad Technical Service Bulletin (NTB13-097J) that covers all 2012 and newer vehicles (including the Murano) for EVAP leak codes P0442, P0455, and P0456. This bulletin acknowledges the commonality of the issue and provides dealers with a diagnostic flowchart that emphasizes starting with the gas cap and warns against wasting time with test drives. It also notes that any parts replaced under warranty for these codes are subject to inspection, and functional parts will result in a charge-back to the dealer, highlighting the importance of accurate diagnosis.
• Owner Forum Consensus: Gas Cap and Vent Valve: Across forums like nissanmurano.org and The Nissan Path, owners consistently report that the P0442 code is resolved by either replacing the gas cap with an OEM part or replacing the EVAP canister vent control valve. Many users report that aftermarket gas caps fail to resolve the issue.

Mechanic-Grade Diagnostic Values

• EVAP Canister Purge Valve Resistance — expected: 15 - 30 Ohms. Failure: A reading of infinite resistance (open) or near zero (short) indicates a failed solenoid coil.
• EVAP Canister Vent Control Valve Resistance — expected: 20 - 50 Ohms. Failure: A reading outside this range, especially an open circuit (infinite ohms), indicates the internal coil has failed.
• EVAP Canister Vent Control Valve Connector Voltage — expected: Approximately 12V (battery voltage) on one of the two pins with the ignition key in the ON position.. Failure: No voltage suggests a wiring issue or a blown fuse, preventing the valve from being energized.
• Fuel Tank Pressure (FTP) Sensor Voltage — expected: 1.0 - 4.0 Volts. Failure: A voltage reading outside of this range can indicate a faulty sensor, which may trick the ECU into setting a false leak code.

Hidden / Shadow Codes Worth Checking

• Mode 6, Monitor ID $3B: This monitor ID specifically relates to the EVAP system's self-test for a 0.040" leak, which is the threshold that triggers a P0442 code. Reviewing the test results can confirm the failure without waiting for the monitor to run again. (see via An advanced OBD-II scan tool that supports Mode 6 data viewing.)

Scan Tool Commands That Help

• Nissan CONSULT-III plus: EVAP System Test / Active Test: Vent Valve Close — This command is essential for diagnosis. It manually closes the normally-open vent valve, which is the first step in sealing the EVAP system to perform a pressure, vacuum, or smoke test to find the leak's source.
• Advanced Bidirectional Scan Tool (e.g., Autel, THINKCAR): Vent Valve On/Off Command — Used to quickly test the functionality of the vent valve solenoid. By commanding the valve on and off, a technician can listen for an audible 'click', which confirms the solenoid's electrical coil and plunger are working.

Wiring & Ground Locations

• EVAP Purge Valve Connector — In the engine bay, on top of the intake plenum, typically on the driver's side.. A loose or corroded connector here can prevent the purge valve from operating correctly, potentially causing it to remain slightly open and create a leak path.
• EVAP Vent Control Valve Connector — At the rear of the vehicle, connected to the vent valve which is mounted on or next to the charcoal canister.. This connector and its wiring are exposed to road spray and debris, making them susceptible to corrosion or damage that can cause the valve to fail to close, resulting in a leak code.
• Engine Compartment Fuse Box — Under the hood, typically a black box located near the battery. The Murano has two fuse boxes in this area.. The EVAP system solenoids are powered by circuits protected by fuses in this box. A blown fuse will disable a valve, which can lead to a P0442 code.

Real Owner Repair Stories

• YouTube channel 'The DIY Yardie' (2009 Nissan Murano (similar EVAP system design)) — Check Engine Light with code P0442.
  ❌ Tried (didn't work) The owner went straight to the most likely mechanical failure point after the gas cap.
  ✅ What actually fixed it The owner removed the EVAP canister vent control valve, tested it with a 9V battery to confirm the solenoid clicked, then thoroughly cleaned it with water and compressed air to remove dirt that was preventing a proper seal. After reinstalling the cleaned valve, the code was resolved.

"I Checked Everything" — The Actual Cause

• In some cases, a smoke test may pass without showing any leaks, yet the P0442 code persists. There are two primary culprits in this scenario. The first is a faulty Fuel Tank Pressure (FTP) sensor; the system is perfectly sealed, but the sensor is sending incorrect data to the ECU, causing a false leak code. The second common cause is an intermittent gas cap seal that holds pressure during a static test but fails under normal driving vibrations and temperature changes.

OEM Part Supersession History

• 14935-JF00A, 14935-JF00B, 14935-JF00C, 14935-JF00D, 14935-JF00E, 14935-JF01B, 14935-JF01C → 14935-JF02C — Part has been updated multiple times by Nissan to improve reliability and address common failure modes.
  Heads up: The newest part number, 14935-JF02C, is the correct replacement for all previous versions for this vehicle range.
• 14930-JA10A, 14930-JA10B → 14930-JA10D — Updated design for the EVAP Canister Purge Solenoid.

Model Year Variations Within This Range

• 2017-2018 vs 2019-2022: The 2019 model year facelift included minor changes to the EVAP system hoses. For example, one fuel evaporation control hose (P/N 14912-3JA2C) was used on models with a production date up to 11/2018, while a different part (P/N 14912-3JA2B) was used from 11/2018 onward. While functionally similar, using the correct part number is important for proper fitment.