P0440 on the All-New 2024 Infiniti QX80
A P0440 code on your completely redesigned 2024 Infiniti QX80 indicates a general evaporative emission system malfunction. The 2024 QX80 represents a ground-up redesign, moving to a new platform with a twin-turbocharged 3.5L V6 replacing the previous 5.6L V8. The EVAP system has been redesigned alongside the new powertrain, and as with any all-new model, early production units may experience minor component issues that are fully covered under warranty.
First-Year Model Considerations
As a completely new design, the 2024 QX80 may experience EVAP-related issues that are unique to the initial production run. Infiniti and Nissan typically issue technical service bulletins and software calibration updates during the first year to address any manufacturing variances discovered in the field. Your dealer will have access to the latest information specific to the 2024 platform.
Probable Causes
- Gas Cap Seal (30% likelihood) — Whether the 2024 QX80 uses a traditional cap or capless system, the filler neck seal is the easiest check. Ensure a proper seal after refueling. If using a traditional cap, tighten until it clicks.
- Purge Control Solenoid Valve (25% likelihood) — The PCSV on the new twin-turbo V6 manages vapor flow from the canister to the intake system. A manufacturing defect can prevent proper sealing. Warranty replacement.
- Canister Close Valve (CCV) (20% likelihood) — The vent valve on the new platform may have slightly different mounting and routing compared to the previous generation. A factory defect or installation issue can trigger P0440. Warranty replacement.
- EVAP System Software Calibration (10% likelihood) — On an all-new platform, the PCM's EVAP monitoring parameters may need recalibration. Your dealer can check for and apply any available software updates. Warranty service.
- Leak Detection Pump (5% likelihood) — If the redesigned system retains Nissan's active leak detection, a pump defect can generate false readings. Warranty replacement.
- Assembly Connection (5% likelihood) — Early production vehicles occasionally have a vapor line or connector not fully seated. Smoke testing at the dealer will identify the location. Warranty repair.
- Fuel Tank Pressure Sensor (5% likelihood) — An out-of-spec sensor on the new platform. Warranty replacement.
Warranty Coverage
Your 2024 QX80 is protected by Infiniti's 4-year/60,000-mile basic warranty, covering all EVAP system components. The federal emissions warranty provides additional protection on specified parts for 8 years/80,000 miles. All diagnosis and repair for P0440 is at zero cost to you at any Infiniti dealer. Given that this is a redesigned model, your dealer may also document the issue with Infiniti's engineering team as part of their quality feedback process.
Recommended Action
For a brand-new 2024 model, the clear course of action is to schedule a service appointment with your Infiniti dealer. Do not attempt DIY repairs on a vehicle under full warranty — you want the repair documented in Infiniti's service records. Before your appointment, ensure the gas cap is properly sealed. Mention the P0440 code when booking to help the service team prepare. Most repairs are completed in a single visit within 1–3 hours.