Decoding the P0440 on Your 2024 Buick Envision
A P0440 code on your 2024 Buick Envision means an EVAP system malfunction. Your compact luxury SUV is fully covered under GM's warranty for a no-cost dealer repair.
Most Likely Causes
- Fuel Filler Issue (35%) — Not sealed properly. Cost: $0.
- Factory Assembly (22%) — Connection issue. Cost: $0 under warranty.
- Vent Valve Solenoid (15%) — GM common failure. Cost: $0 under warranty.
- Software (12%) — ECM update. Cost: $0 under warranty.
- Purge Valve (10%) — Defect. Cost: $0 under warranty.
- EVAP Hose (6%) — Routing. Cost: $0 under warranty.
Warranty
- Bumper-to-Bumper: 3 years/36,000 miles
- Powertrain: 5 years/60,000 miles
Check the fuel filler. Dealer handles the rest at no cost.
The Verdict
A warranty repair. Check the filler, then schedule a dealer appointment.