Solving P0446 on Your 2024 Buick Envision
A P0446 code on your 2024 Buick Envision signals an EVAP vent control circuit malfunction. The Envision uses a 2.0L turbo engine on a GM platform with an ECM-controlled vent valve solenoid. P0449 is a common GM companion code for this circuit.
Under full warranty, this is a no-cost dealer repair.
Symptoms Present
- Check engine light with P0446
- P0449 companion code may appear
- Fuel fill difficulty
- EVAP readiness monitor incomplete
Top Suspects
- Vent Valve Solenoid Defect (High Likelihood): Manufacturing variation. Warranty-covered.
- ECM Software Calibration (High Likelihood): EVAP monitoring update. Warranty-covered reflash.
- Purge Solenoid Valve (Medium Likelihood): Defective purge valve. Warranty-covered.
- Vent Valve Wiring or Connector (Medium Likelihood): Factory assembly issue. Warranty-covered.
- Gas Cap Seal (Low Likelihood): Factory fit. Warranty-covered.
What to Do
Take your Envision to a Buick dealer. GDS2 diagnostics and all EVAP repairs are free under warranty.
Full Warranty Coverage
Your 2024 Envision is covered by Buick's 3-year/36,000-mile basic and 5-year/60,000-mile powertrain warranty. All EVAP repairs are free.
Safe to Drive?
Yes. P0446 doesn't affect your Envision's turbo engine, AWD, transmission, or any features.