EVAP Canister Vent Solenoid
WARNING: This page does not describe the selected car, but rather 7 other vehicles, including the 2003 GMC Yukon XL, 2003 GMC Sierra, 2003 GMC Cab & Chassis Sierra, 2003 Chevrolet Suburban, and 2003 Chevrolet Silverado. However, it is still accessible from the selected car via links, so may be relevant.
The EVAP canister vent solenoid controls fresh air flow into the EVAP canister. EVAP canister vent solenoid is mounted on frame rail, near fuel tank. See Fig 1 . The solenoid is normally open. The control module will command the solenoid closed during some EVAP tests, allowing the system to be tested for leaks.