Decoding the P0440 on Your 2024 Lexus NX
A P0440 code on your 2024 Lexus NX indicates an EVAP system malfunction. Your compact luxury SUV, now in its third year of the second-generation design, is fully covered under Lexus' comprehensive warranty.
The 2024 NX EVAP System
Available across NX 250, NX 350, NX 350h, and NX 450h+ variants, the EVAP system includes:
- Purge VSV — Vapor flow control
- Canister Close Valve — System sealing for leak tests
- Charcoal Canister — Vapor storage
- Vapor Pressure Sensor — In-tank monitoring
- Fuel Filler System — Fuel system seal
Most Likely Causes
- Fuel Filler Issue (35%) — Gas cap not seated. Cost: $0.
- Factory Issue (20%) — Assembly connection. Cost: $0 under warranty.
- Purge VSV Defect (15%) — Vacuum switching valve fault. Cost: $0 under warranty.
- Software Update (13%) — ECM calibration. Cost: $0 under warranty.
- CCV Issue (10%) — Canister close valve. Cost: $0 under warranty.
- EVAP Line Issue (7%) — Hose or connection. Cost: $0 under warranty.
Lexus Warranty
- Basic: 4 years/50,000 miles
- Powertrain: 6 years/70,000 miles
Check the gas cap first. If the code persists, your Lexus dealer handles everything at no cost.
The Verdict
A P0440 on a 2024 NX is a warranty repair under Lexus' 4-year/50,000-mile coverage. Check the gas cap, then let the dealer diagnose with Techstream. Toyota/Lexus quality means this is almost certainly a one-time minor issue.