EMISSION CONTROL SYSTEM


  1. OUTLINE


    1. Exhaust Emission Control System


      1. Three-Way Catalytic converters (TWCs) are used in the exhaust manifold converter sub-assembly and the front exhaust pipe assembly.

      2. The ECM performs the air fuel ratio feedback control based on signals from the air fuel ratio sensor and the 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. An air fuel ratio sensor and an oxygen sensor heater control, which maintain the temperature of the respective sensors at an appropriate level, are used to improve the detection accuracy of oxygen concentration in exhaust gas.

    2. Exhaust Gas Recirculation (EGR) Control System


      1. EGR control, together with the high efficiency EGR cooler assembly, offers high fuel efficiency. In addition, the E.F.I. vacuum sensor assembly detects the intake manifold pressure. This information is used to diagnose EGR valve assembly operation.

    3. Blowby Gas Ventilation System


      1. A blowby gas ventilation system, which efficiently ventilates blowby gas containing HC from the crankcase, is used.

    4. Evaporative Emission Control System


      1. An evaporative emission control, which regulates the purge flow of evaporative emission (HC) into the charcoal canister in accordance with the engine conditions, is used.