FUEL SYSTEM


  1. FUNCTION OF MAIN COMPONENTS


    1. The D-4 system has the following components and functions:

      Component Function
      Fuel Pump Assembly (for Low Pressure) Sends fuel (400 kPa) from the fuel tank assembly to the fuel pump assembly (for high pressure).
      Fuel Pump Assembly (for High Pressure) Increases the pressure of the fuel from the fuel pump assembly (for low pressure) to a pressure of 4 to 13 MPa and sends it to the fuel delivery pipe sub-assembly.
      Spill Control Valve Closes and opens the fuel flow path to the fuel delivery pipe sub-assembly in accordance with signals from the EDU (Injector Driver).
      Fuel Delivery Pipe Sub-assembly Delivers the high-pressure fuel to the fuel injector assembly.
      Fuel Pressure Pulsation Damper Assembly Reduces fuel pressure fluctuation (pulsation) and noise.
      Fuel Pressure Sensor Senses the fuel pressure and outputs a signal to the ECM.
      Fuel Relief Valve Assembly If the fuel pressure in the delivery pipe is abnormally high, the fuel relief valve assembly discharges some of the fuel to the fuel tank assembly in order to limit the pressure.
      Fuel Injector Assembly Injects a calculated (by the ECM) quantity of 4 to 13 MPa (high pressure) fuel directly into the combustion chamber.
      Cold Start Fuel Injector Assembly* Injects fuel into the intake manifold when the engine is started at low engine coolant temperature to improve cold-starting performance.
      EDU (Injector Driver) Transforms signals sent from the ECM (fuel injection request and high-pressure fuel injection volume control) into high-pressure and high-voltage operation signals in order to operate the fuel injector assemblies and spill control valve at high-speed.
      ECM Depending on the vehicle condition, and based on signals from various sensors, the ECM calculates the optimal injection timing and volume, and controls the fuel injector assembly and fuel pump assembly (for high pressure).

      *: Models with cold start fuel injector assembly

  2. FUNCTION


    1. The Direct injection 4-stroke gasoline engine (D-4) system is an engine in which highly pressurized fuel is injected directly into the combustion chamber. Fuel injection timing, air-fuel ratio, throttle valve opening angle, etc. are controlled in a comprehensive manner, realizing both high output and low emissions.

    2. The fuel atomized by the high-pressure slit nozzle fuel injector assembly is injected into the combustion chamber, spreading wide and winding up a mass of the air. Highly pressurized and atomized fuel spreads through the whole combustion chamber by its own energy, without depending on the air stream, then is mixed with the intake air, achieving the ideal combustion in all driving ranges.

      A0120BYC02
      *1 Fuel Injector Assembly - -