EMISSION CONTROL SYSTEM(for Korea)


  1. OUTLINE


    1. Exhaust Emission Control System


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

      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.

    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. This system has the following controls:


        • Purge flow control

        • Onboard Refueling Vapor Recovery (ORVR)

        • Evaporative emission (EVAP) leak check

      2. The charcoal canister assembly and trap canister store the fuel vapor that has been created in the fuel tank assembly.

      3. This system consists of a purge VSV, charcoal canister assembly, canister pump module 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.

      5. In this system, the ECM checks for evaporative emission leaks and stores Diagnostic Trouble Codes (DTCs) in the event of a malfunction. An evaporative emission leak check consists of an application of vacuum to the evaporative emission system and the ECM monitoring the system for changes in pressure in order to detect a leak. For details of DTC, refer to the repair manual.

      6. A canister pressure sensor is included in the canister pump module.

      7. A No. 1 charcoal canister filter is provided in the fresh air line.

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