Investigating P0442 on Your 2022 Buick Enclave
A P0442 code on your 2022 Buick Enclave indicates the engine control module detected a small leak in the evaporative emission system. The Enclave uses GM's proven EVAP design, making diagnosis well-established and systematic.
Enclave EVAP System
The 2022 Enclave's 3.6L V6 uses GM's standard EVAP system with a purge solenoid valve, vent valve solenoid, and charcoal canister. The ECM monitors pressure to detect leaks of approximately 0.020 inches. As a three-row crossover, the Enclave has moderate EVAP routing from its rear fuel tank.
Most Likely Causes
- Gas cap seal wear (40%) — After two to three years, the gasket may have minor wear or contamination.
- EVAP hose connection issue (25%) — Vapor line connections can loosen from vibration.
- Vent valve solenoid failure (15%) — GM's vent valve solenoid can develop sealing issues over time.
- Charcoal canister fault (10%) — Road debris damage to the underbody canister.
- Purge solenoid valve seal (10%) — Internal seal degradation.
Diagnostic Steps
Replace the gas cap first. If the code persists, a Buick dealer with GDS2 can run targeted EVAP component tests. A smoke test provides visual leak confirmation.
Repair Costs
- Gas cap: $15–$40
- EVAP hose repair: $80–$230
- Vent valve solenoid: $120–$260
- Charcoal canister: $230–$460
- Purge solenoid valve: $120–$260
- Smoke test: $80–$150
Warranty
Your 2022 Enclave is within Buick's 4-year/50,000-mile basic warranty (Buick offers an enhanced warranty vs base GM). The 6-year/70,000-mile powertrain warranty and federal 8-year/80,000-mile emissions warranty provide additional coverage. Contact your Buick dealer for warranty repair.