P0442 on 2007-2014 Nissan Maxima: EVAP Small Leak Causes and Fixes

What's Unique About the 2007-2014 Nissan MAXIMA

On this generation of Nissan Maxima, the EVAP system components, particularly the vent control valve located at the rear of the car, are known to fail due to exposure to road debris and moisture. For the 7th generation (2009-2014), this valve is notoriously difficult to access as it is located above the rear subframe, often requiring the subframe to be lowered for replacement. 🎬 Watch: How to replace the vent solenoid on 7th gen Maximas. Nissan has issued several Technical Service Bulletins (TSBs) that acknowledge EVAP leak codes across its lineup, often starting the diagnosis with the gas cap, which is a very common failure point. The vent valve and purge valve are also frequent culprits, with many owners successfully resolving the code by replacing one of these parts.

Diagnostic Flowchart

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

Generation note: This range covers the end of the 6th generation (2007-2008) and the entire 7th generation (2009-2014) Maxima. While the underlying causes for P0442 are similar, the exact location and part numbers for components like the EVAP vent control valve may differ slightly. For example, the 7th-gen valve is located above the rear subframe, attached to the canister, making it more difficult to access than the 6th-gen version. The 6th-gen valve is in a similar area but may have a slightly different removal process.

Symptoms You May Notice

• Check Engine Light is on
• A faint smell of fuel, especially when parked in an enclosed space like a garage.
• A "Loose Fuel Cap" warning message on the dashboard.
• Slightly reduced fuel economy.
• Difficulty starting the engine immediately after refueling (a symptom often linked to a stuck-open purge valve).

Most Likely Causes

1. Loose or Faulty Gas Cap 🔴 High Probability This is the most common cause for any EVAP code on any vehicle. Nissan TSB NTB09020F and NTB13-097J specifically call this out as a primary and likely cause for the 2007-2011+ models. The rubber seal on the cap can crack or degrade over time.
   How to confirm: Ensure the gas cap is tightened until it clicks at least once. Inspect the cap's rubber seal for cracks, dirt, or damage. If the seal is compromised, the cap needs replacement. Many owners on forums confirm this simple fix resolves the issue.
   Typical fix: Tighten or replace the gas cap. It is highly recommended to use a genuine OEM Nissan cap, as aftermarket caps are known to cause sealing issues.
   Est. part cost: $20-$40
2. Failed EVAP Canister Vent Control Valve 🟡 Medium Probability Located at the rear of the vehicle near the charcoal canister, this valve is exposed to road salt and moisture, causing it to stick open or fail electronically. This is a well-documented failure point on many Nissan models, including the Maxima, Altima, and Murano.
   How to confirm: A mechanic can command the valve to open and close with a diagnostic scan tool. A DIY method is to remove the valve and apply 12V power to its terminals to see if the solenoid clicks; a lack of a click indicates failure. A smoke test is the most definitive way to confirm a leak at the valve.
   Typical fix: Replace the EVAP canister vent control valve. On 7th-gen Maximas (2009-2014), this is a difficult job as the valve is tucked above the rear subframe. Some owners partially drop the rear subframe to gain access. Lubricating the new valve's O-ring with silicone or petroleum jelly is recommended for easier installation.
   Est. part cost: $50-$120
3. Failed EVAP Canister Purge Volume Control Solenoid/Valve 🟡 Medium Probability This valve is located in the engine bay and controls the flow of fuel vapors from the canister to the engine. It can get stuck open or closed, creating a leak path or blocking flow. A common symptom of it being stuck open is difficulty starting after refueling.
   How to confirm: With the engine off, disconnect the vapor line from the purge valve. If you can blow through it, it's stuck open and needs to be replaced. A scan tool can also be used to command it open and closed to check for function.
   Typical fix: Replace the purge valve. This is typically an easy repair located on or near the engine's intake manifold.
   Est. part cost: $40-$150
4. Cracked or Disconnected EVAP Hoses ⚪ Low Probability Over time, the rubber hoses in the EVAP system can become brittle, dry-rot, and crack, creating small leaks, especially at connection points.
   How to confirm: A visual inspection may reveal obvious cracks, especially at connection points. The most effective method is a smoke test, which forces smoke through the EVAP system, making even tiny leaks visible.
   Typical fix: Replace the damaged section of hose. This can range from a simple, inexpensive fix to a more complex one if the hose is in a hard-to-reach area.
   Est. part cost: $10-$50

Rare But Worth Checking

• Cracked Charcoal Canister: The plastic housing of the canister can develop hairline cracks from age or impact from road debris. This is usually found with a smoke test.
• Rusted Fuel Filler Neck: In regions with heavy road salt use, the metal fuel filler neck can rust and develop pinhole leaks where the gas cap seals, which will trigger a P0442 code. This can be confirmed by visually inspecting the filler neck for corrosion and can often be cleaned with a wire brush as a temporary fix.
• Leaking Vent Control Valve O-ring: Sometimes the vent control valve itself is functional, but the O-ring that seals it to the charcoal canister has failed. Nissan TSB NTB17-082E addresses this specific issue for code P0456, but the principle applies to P0442 as well. Always replace the O-ring when replacing the valve.

Diagnosis Steps

1. Check the Gas Cap: Remove and reinstall the gas cap, ensuring it clicks several times. Clear the code and drive for a few days. If it returns, inspect the cap's seal for damage and consider replacing it with an OEM part. Check the fuel filler neck for rust or debris that could prevent a good seal.
2. Visual Inspection: Inspect all accessible EVAP hoses and lines from the engine bay to the rear of the vehicle for obvious cracks, loose connections, or damage. Pay close attention to the connections at the purge solenoid and charcoal canister.
3. Test the Purge Valve: Locate the purge valve in the engine bay. With the engine off, disconnect the hose from the valve that leads to the intake manifold. Try to blow through the valve. If air passes, it is stuck open and must be replaced.
4. Test the Vent Valve: Locate the vent valve at the rear of the car. Apply 12V power to its terminals. A healthy valve will make an audible 'click'. If it doesn't click, it has failed electronically. Even if it clicks, it may still be leaking internally.
5. Perform a Smoke Test: This is the most effective way to find the source of the leak. A smoke machine is connected to the EVAP system service port. The system is filled with a harmless, visible smoke under low pressure. Smoke will exit from any leak point, pinpointing the exact location of the fault, whether it's a hose, valve, canister, or the fuel filler neck.

Parts You'll Likely Need

• Fuel Filler Cap (OEM #17251-1VZ0A) — This is the most frequent cause. The seal wears out over time, causing a leak. Nissan specifically recommends checking this first.
  Trusted brands: Nissan (OEM)
  OEM price range: $25-$40
  Aftermarket price range: $15-$25
• EVAP Canister Vent Control Valve (OEM #14935-JF02C) — A very common failure item on Nissans due to its location under the car, where it's exposed to the elements and can get stuck or fail electronically.
  Trusted brands: Nissan (OEM), Dorman, Hitachi
  OEM price range: $60-$90
  Aftermarket price range: $40-$80
• EVAP Canister Purge Volume Control Valve (OEM #14930-JA10A) — This valve in the engine bay can fail and get stuck open, creating a leak path. It's a common repair for P0442, especially if hard-starting occurs after refueling.
  Trusted brands: Nissan (OEM)

Related Codes That Often Appear With This One

• P0455 — Indicates a large EVAP leak. If both codes are present, it could point to a component that has failed completely, such as a vent valve stuck wide open or a very loose/missing gas cap.
• P0456 — Indicates a very small EVAP leak. Seeing P0442 and P0456 together suggests an intermittent or borderline leak that the computer is having trouble classifying. Nissan groups these codes together in their service bulletins.

Technical Service Bulletins (TSBs) & Recalls

• NTB13-097J
• NTB09020F
• NTB17-082E

Platform-Specific Known Issues

• Nissan Technical Service Bulletin NTB13-097J addresses diagnostic procedures for P0442, P0455, and P0456, emphasizing that a test drive is not an effective diagnostic step and providing a specific flowchart for technicians. It explicitly states that a loose fuel cap is a potential cause.
• Nissan TSB NTB09020F specifically identifies a loose fuel fill cap as a primary cause for P0442 on 2007-2011 models.
• Multiple owner accounts and repair videos for the 7th generation (2009-2014) Maxima confirm the difficult location of the EVAP canister vent valve above the rear subframe, requiring extra labor to access.

Mechanic-Grade Diagnostic Values

• EVAP Canister Purge Volume Control Valve Resistance — expected: 15 to 30 Ohms is a general range for many solenoids.. Failure: A reading of 0 Ohms (short circuit) or infinite/OL (open circuit) indicates a failed solenoid coil.
• EVAP Canister Vent Control Valve Resistance — expected: Generally falls between 20 and 50 Ohms.. Failure: A reading significantly outside this range, or showing as open/shorted, points to a bad solenoid coil.
• EVAP Canister Vent Control Valve Power Supply — expected: 12V (battery voltage) should be present at one of the two pins on the valve's connector when the ignition is ON.. Failure: No voltage suggests a wiring issue or a blown fuse. The fuse for the EVAP system is often located in the IPDM E/R (Intelligent Power Distribution Module Engine Room).

Scan Tool Commands That Help

• Nissan CONSULT / Advanced Bidirectional Scanner (e.g., Autel, Snap-on): EVAP System Leak Test / Vent Valve Control — This function allows a technician to command the EVAP vent valve to close, sealing the system. This is a critical step before performing a smoke test or a vacuum decay test to check for leaks. It directly tests the functionality of the vent valve solenoid and wiring.
• Nissan CONSULT / Advanced Bidirectional Scanner (e.g., Autel, Snap-on): Purge Volume Control Valve Test — This command cycles the purge valve on and off, allowing a technician to hear it click and verify its mechanical operation. While listening for the click, the technician can also check if the valve is sealing properly by feeling for vacuum on the canister side port.

Wiring & Ground Locations

• EVAP Canister Vent Control Valve Connector — At the rear of the vehicle, plugged directly into the vent valve which is mounted on the charcoal canister. The canister is located above the rear subframe.. This 2-pin connector provides power and ground to operate the vent valve. Corrosion on the pins or damage to the harness in this exposed location can prevent the valve from closing, creating a permanent leak condition that sets code P0442.
• EVAP Canister Purge Volume Control Solenoid Connector — In the engine bay, connected to the purge valve which is typically mounted on or near the intake manifold.. A loose connection or damaged wire at this connector can prevent the purge valve from operating correctly. If it fails to close, it creates a vacuum leak and can trigger a P0442.
• Ground E9 — Located at the left rear of the engine compartment for the 2009 Maxima.. This is a potential grounding point for engine bay components. A poor ground connection can cause erratic behavior in various sensors and solenoids, including the EVAP purge valve.
• ECM (Engine Control Module) — For the 2009 Maxima, it is located in the left front of the engine compartment.. The ECM provides the ground signal to activate both the purge and vent valves. A fault in the ECM driver circuit, though rare, could be a root cause if the valves and wiring test good.

Real Owner Repair Stories

• Maxima.org forum user (2011 Nissan Maxima SV) — P0455 (Large Leak) code, gas smell, and "loose fuel cap" warning on the dash.
  ❌ Tried (didn't work) Replacing the gas cap.
  ✅ What actually fixed it The user replaced the EVAP canister vent control valve. They noted that the service manual indicated the gas tank or stabilizer bar might need removal, but they were seeking an easier way to access it, confirming the difficult location on the 7th generation models.

"I Checked Everything" — The Actual Cause

• In some cases, a smoke test may not reveal a leak, especially if the failure is intermittent or related to a component that only fails under specific conditions (like temperature or vibration). A common scenario is an EVAP vent valve that passes a smoke test (seals correctly when closed by a scan tool) but fails to operate reliably on its own, or has a very slow, borderline leak that is difficult to detect with smoke. If a smoke test is clean, the next step is often to test the valves electrically (resistance) and mechanically (applying 12V to listen for a click) or simply replace the most likely component, which is often the vent control valve.

OEM Part Supersession History

• 14935-JF00A → 14935-JF00B, 14935-JF00C, 14935-JF00D, 14935-JF00E, and finally 14935-JF02C — Revisions by the manufacturer to improve reliability and address failure points of the EVAP Canister Vent Control Valve.
  Heads up: All listed part numbers are generally interchangeable, with the latest version (14935-JF02C) being the recommended replacement.

Model Year Variations Within This Range

• 2009-2014 (7th Generation): The EVAP canister vent control valve is located above the rear subframe, making access significantly more difficult than on the 2007-2008 models. Service procedures may require lowering the rear stabilizer bar or subframe to gain enough clearance to remove and replace the valve.