Investigating P0440 on Your 2022 Infiniti QX60
A P0440 code on your 2022 Infiniti QX60 reveals that the EVAP (evaporative emission control) system has a general malfunction. The completely redesigned 2022 QX60 moved to Nissan's global platform with a new 3.5L V6 and 9-speed automatic transmission, replacing the previous CVT. While the platform is new, the EVAP system follows Nissan's established architecture with some Infiniti-specific refinements.
QX60 EVAP System Components
The 2022 QX60's EVAP system consists of a traditional gas cap, charcoal canister, purge control solenoid valve (PCSV), canister close valve (CCV — Nissan's term for the vent valve), leak detection pump, fuel tank pressure sensor, and vapor lines connecting all components. Nissan's EVAP monitoring strategy uses both the leak detection pump and fuel tank pressure sensor to verify system integrity during specific driving and key-off conditions.
Ranked Causes for the QX60
- Gas Cap Issue (25% likelihood) — The 2022 QX60 uses a traditional threaded gas cap. A loose, cross-threaded, or worn cap is the easiest cause to check. Inspect the rubber gasket for cracks or deformation. Replacement cost: $12–$30.
- Purge Control Solenoid Valve (25% likelihood) — The PCSV on Nissan/Infiniti vehicles controls vapor flow from the canister to the intake manifold. Internal leaks or electrical failure will prevent proper EVAP operation. Located in the engine bay for relatively easy access. Replacement cost: $40–$85. Labor: $70–$140.
- Canister Close Valve (CCV) (20% likelihood) — Nissan's equivalent of a vent valve solenoid, the CCV controls airflow through the charcoal canister. Located near the canister at the rear of the vehicle, it's exposed to the elements and can fail mechanically or electrically. Replacement cost: $50–$100. Labor: $100–$200.
- Leak Detection Pump (15% likelihood) — Unique to Nissan/Infiniti EVAP systems, the leak detection pump actively tests for leaks by pressurizing the system. A failed pump can either cause false P0440 codes or fail to detect real leaks. Replacement cost: $80–$180. Labor: $120–$220.
- EVAP Line or Connection Leak (10% likelihood) — Cracked hoses, loose connections, or damaged fittings throughout the vapor line network. Professional smoke testing is the most effective diagnostic method.
- Charcoal Canister (5% likelihood) — Saturation from fuel overfilling or physical damage. Replacement cost: $120–$300. Labor: $120–$200.
Nissan/Infiniti Diagnostic Approach
Infiniti dealers use CONSULT diagnostic software for comprehensive EVAP system testing, including solenoid actuation, leak detection pump operation, and real-time pressure monitoring. Key data points include fuel tank pressure during seal tests, PCSV and CCV response times, and leak detection pump operation results. Aftermarket scan tools with Nissan-enhanced protocols can provide similar access for independent shops.
Cost and Warranty Information
The 2022 QX60 is covered by Infiniti's 4-year/60,000-mile basic warranty. Given the 2022 model year, verify your coverage before paying for repairs. If within warranty, all EVAP diagnosis and repair is covered at your Infiniti dealer. Out-of-warranty repair costs range from $12 for a gas cap to $500+ for leak detection pump or charcoal canister replacement at dealer rates.
DIY Feasibility
Gas cap replacement is simple DIY. The purge control solenoid valve is accessible in the engine bay and replaceable with basic tools. The canister close valve and leak detection pump are more involved due to their rear-of-vehicle location but are still manageable for experienced DIYers. A proper EVAP smoke test, however, requires professional equipment and is recommended for accurate diagnosis before replacing parts.