Sonata GL V6-2.5L (1999)
On-Board Refueling Vapor Recovery System: Description and Operation
EVAPORATIVE & ORVR EMISSION CONTROL SYSTEM DESCRIPTION
On-Board Refueling Vapor Recovery (ORVR) system is properly designed to prevent the fuel tank vapor(HC) emission during refueling at the gas
station.
This system consists of fill vent valve (ORVR), fuel shut-off valve, fuel cut valve(roll over), two way valve (pressure/vacuum relief), fuel liquid-vapor
separator which is installed beside the filler pipe, charcoal canister which is mounted under the rear floor LH side member with protector, tubes and
miscellaneous connections.
During refueling, the flow and column of the refueling fuel draws the ambient air into the filler pipe so as not to emit fuel vapor in the air. The fuel vapor
in the tank is then forced to the canister via the fill vent valve and the fuel liquid/vapor separator which isolates liquid fuel ingredient and transfers the
pure vapor to the carbon canister.
While the engine is operating, the trapped vapor emission in the canister is drawn and fed by the intake manifold vacuum into the engine combustion
chamber. According to this purge process, the carbon canister is purged and recovers its adsorbing capability.
OVERFILL LIMITER (TWO WAY VALVE)
To inspect the overfill limiter (two-way valve), refer to Fuel tank.
