TrailBlazer 4WD L6-4.2L VIN S (2002)
Canister Vent Valve: Description and Operation
EVAP Vent Valve
The EVAP vent valve (1) controls fresh airflow into the EVAP canister. The EVAP vent valve is a normally open valve. The PCM will command the
valve closed during some EVAP tests, allowing the system to be tested for leaks.
