2 GENERAL 2000 FEATURES GENERAL 2000 FEATURES ENGINE EMISSION CONTROL SYSTEM The method for detecting evaporative emission leaks has been changed from the previous internal pressure monitor type to the vacuum type. The vacuum pressure monitoring type forcefully introduces the purge vacu- um into the entire system and a leak is detected by monitoring the transitions in pressure. The changes associated with this system are as follows: A VSV for canister closed valve has been added to the fresh air introduction line. The 3-way VSV for vapor pressure sensor has been discontinued, and a VSV for pressure switching valve has been added.
The sensing position of the vapor pressure sensor has been changed from the charcoal canister to the fuel tank in order to enhance the precision of the vapor pressure sensor. The fresh air valve characteristics of the charcoal canister have been changed. DTCs (Diagnostic Trouble Codes) have been added. For details on the DTCs, refer to the Repair Manual for each model. This system has been provided on the LS400, SC400/300, ES300 and RX300. Vapor Pressure Sensor VSV (for Pressure Switching Valve) Charcoal Canister VSV (for Canister Closed Valve) VSV (for EVAP) Fuel Tank Purge Line Fresh Air Line Drain 170EG08