EMISSION CONTROL SYSTEM


  1. OUTLINE


    1. Exhaust Emission Control System


      1. Three-Way Catalytic converters (TWCs) are used in order to reduce exhaust emissions.

      2. The ECM performs air fuel ratio feedback control based on signals from the air fuel ratio sensor and the heated oxygen sensor, and controls the fuel injection amount so that the air fuel ratio comes close to the stoichiometric air fuel ratio, at which the highest purifying efficiency of CO, HC and NOx is obtained.

      3. Air fuel ratio sensor and heated oxygen sensor heater control, which maintains the temperature of the respective sensors at an appropriate level, is used to improve the detection accuracy of oxygen concentration in the exhaust gas.

    2. Exhaust Gas Recirculation (EGR) System


      1. EGR control, together with the high efficiency EGR cooler assembly, offers high fuel efficiency and power output. In addition, the vacuum sensor assembly detects the intake manifold pressure. This information is used to adjust the EGR volume to its optimum level.

    3. Blowby Gas Ventilation System


      1. A blowby gas ventilation system is used. This system reduces emissions by forcibly drawing blowby gas, which includes a large amount of HC, into the intake manifold for combustion.

    4. Evaporative Emission Control System


      1. The evaporative emission control system prevents the fuel vapor that is created in the fuel tank assembly from being released directly into the atmosphere.

      2. The canister stores the fuel vapor that has been created in the fuel tank assembly.

      3. This system consists of a purge VSV, canister and ECM.

      4. The ECM controls the purge VSV in accordance with the driving conditions in order to direct the fuel vapor into the engine, where it is burned.