EMISSION CONTROL SYSTEM


  1. FUNCTION OF MAIN COMPONENTS


    1. The main components of the emission control system are as follows:

      Component Function
      Exhaust Emission Control System ECM Determines an optimal fuel injection volume based on the signals from various sensors.
      Three-Way Catalyst (TWC) Reduces CO, HC and NOx in the exhaust gas.
      Oxygen Sensor Detects the oxygen concentration in the exhaust emissions by measuring the electromotive force generated in the sensor itself. For details, see the 1GR-FE ENGINE CONTROL section.
      Air Fuel Ratio Sensor
      Evaporative Emission Control System ECM Sends signals to the VSV (for EVAP) to control the purge flow.
      Charcoal Canister Sub-assembly Contains activated charcoal to absorb the fuel vapor created in the fuel tank.
      Duty Vacuum Switching Valve (for EVAP) Opens in accordance with the signals from the ECM when the system is purging, in order to send the fuel vapor that was absorbed by the charcoal canister into the intake manifold.