Investigating the P0440 on Your 2024 GMC Canyon
A P0440 code on your 2024 GMC Canyon — redesigned for 2023 on a new platform — means the ECM has detected an EVAP system malfunction. Your second model year on the new platform benefits from first-year refinements, and the truck is fully covered under warranty.
The New Canyon's EVAP System
The 2024 Canyon features the 2.7L turbo four-cylinder engine on GM's new mid-size truck platform:
- Vent Valve Solenoid — Controls system venting and seals for leak tests
- Purge Solenoid Valve — Routes fuel vapors to the turbo engine's intake
- Charcoal Canister — Frame-mounted vapor storage
- Fuel Tank Pressure Sensor — EVAP diagnostic monitoring
- Capless Fuel Filler — Spring-loaded internal sealing system
Most Likely Causes
- Capless Filler Debris (33%) — Dirt or debris preventing the internal flap from sealing. Off-road and work site use increases contamination risk. Cost: $0 to clean.
- Factory Assembly Issue (20%) — EVAP connection not fully seated. Cost: $0 under warranty.
- Vent Valve Solenoid (18%) — GM's common weak point. Cost: $0 under warranty.
- Software Calibration (12%) — ECM refinement. Cost: $0 under warranty.
- Purge Valve Defect (10%) — Factory defect. Cost: $0 under warranty.
- EVAP Hose Issue (7%) — Routing or connection. Cost: $0 under warranty.
Warranty Coverage
- Bumper-to-Bumper: 3 years/36,000 miles
- Powertrain: 5 years/60,000 miles
Inspect the capless filler with a flashlight. Clean any debris. If the code persists, schedule a dealer appointment.
The Verdict
The P0440 on your 2024 Canyon is a warranty repair. The capless filler is the most likely culprit — especially on trucks used off-road or at job sites. Clean it first, then let the dealer handle any persistent codes at no cost.