Yukon/Denali 4WD V8-5.3L VIN T (2004)
Refueling Vapor Recovery System: Description and Operation
ON-BOARD REFUELING VAPOR RECOVERY SYSTEM (ORVR)
The On-Board Refueling Vapor Recovery System (ORVR) is an on-board vehicle system designed to recover fuel vapors during the vehicle refueling
operation. The flow of liquid fuel down the fuel filler pipe provides a liquid seal which prevents vapor from leaving the fuel filler pipe. An evaporative
emission (EVAP) pipe transports the fuel vapor to the EVAP canister for use by the engine.
