EMISSION CONTROL SYSTEM


  1. OUTLINE


    1. Exhaust Emission Control System


      1. Three-Way Catalytic converters (TWCs) are used to reduce gas emissions.

      2. The exhaust manifold converter sub-assembly is positioned directly below the turbocharger sub-assembly to improve TWC warm-up performance.

      3. Precise air-fuel ratio control is made possible by positioning the air fuel ratio sensor upstream of the TWC of the exhaust manifold converter sub-assembly, and positioning the oxygen sensor in the front exhaust pipe assembly.

      4. Based on the signals from the air fuel ratio sensor and oxygen sensor, the ECM controls the fuel injection volume in order to optimize the emissions in the exhaust gas.

      5. 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. 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 charcoal canister stores the fuel vapor that has been created in the fuel tank assembly.

      3. This system consists of a purge VSV (No. 1 vacuum switching valve assembly), charcoal canister and ECM.

      4. The ECM controls the purge VSV (No. 1 vacuum switching valve assembly) in accordance with the driving conditions in order to direct the fuel vapor into the engine, where it is burned.

      5. A No. 1 check valve is used between the purge VSV (No. 1 vacuum switching valve assembly) and intake port to prevent intake air from flowing back toward the charcoal canister due to the turbo pressure.