SFI SYSTEM


  1. FUNCTION


    1. The Dual VVT-i system is designed to control the intake and exhaust camshafts within a range of 43° and 40° respectively (of Crankshaft Angle) to provide valve timing that is optimally suited to engine operating conditions. This improves torque in all the speed ranges as well as increasing fuel economy, and reducing exhaust emissions.

      A00YYDAC01
      *1 Camshaft Timing Oil Control Valve Assembly (Exhaust) *2 Camshaft Timing Oil Control Valve Assembly (Intake)
      *3 Camshaft Position Sensor (Exhaust) *4 Camshaft Position Sensor (Intake)
      *5 Engine Coolant Temperature Sensor *6 Crank Position Sensor
      *7 ECM *8

      • Intake Mass Air Flow Meter Sub-assembly

      • Throttle Position Sensor
      A00YY2CE01

    2. The VVT-i system delivers excellent benefits in the different operating conditions as follows:


      1. During Idling

        A00YYH9E01
        Objective Effect
        Reducing overlap to reduce blow back to the intake side

        • Stabilized idling speed

        • Better fuel economy

      2. At Light Load

        A00YY9BE01
        Objective Effect
        Reducing overlap to reduce blow back to the intake side Ensured engine stability

      3. At Medium Load

        A00YYJKE01
        Objective Effect
        Increasing overlap to increase internal EGR reduce pumping loss

        • Better fuel economy

        • Improved emission control

      4. In Low to Medium Speed Range with Heavy Load

        A00YYSIE01
        Objective Effect
        Advancing the intake valve close timing for volumetric efficiency improvement Improved torque in low to medium speed range

      5. In High Speed Range with Heavy Load

        A00YY8AE01
        Objective Effect
        Retarding the intake valve close timing for volumetric efficiency improvement Improved output

      6. At Low Temperatures

        A00YYH9E01
        Objective Effect
        Reducing overlay to reduce blow back to the intake side stabilizes the idling speed at fast idle

        • Stabilized fast idle speed

        • Better fuel economy

      7. Starting Engine and Stopping Engine

        A00YYH9E01
        Objective Effect
        Reducing overlap to minimize blow back to the intake side Improved startability