LS400 – NEW FEATURES 6 NEW FEATURES ENGINE 1. Fuel System ORVR System The ORVR (On-Board Refueling Vapor Recovery) is a system that uses a charcoal canister, which is pro- vided onboard, to recover the fuel vapor that is generated during refueling. This reduces the discharge of fuel vapor into the atmosphere. Intake Air Chamber Fuel Tank Over Fill Check Valve VSV (for EVAP) ECM Vapor Pressure Sensor VSV (for Canister Closed Valve) Vapor Fuel Inlet Pipe VSV (for Pressure Switching Valve) Charcoal Canister Fuel Fuel Pump 173LS01 1) Operation When the fuel tank cap is removed, atmosphere applies to the fuel tank over fill check valve’s chamber A.
Refueling causes the internal pressure of the fuel tank to increase, the vapor flows to the charcoal can- ister while maintaining valve B pressed, thus allowing the vapor to become absorbed by the charcoal can- ister. When the tank is full, valve C closes, thus shutting off the passage to the charcoal canister. Valve B Chamber A From Fuel Inlet Pipe (Atmosphere) To Charcoal Canister Vapor Valve C 159EG09 Fuel Tank Over Fill Check Valve