SFI SYSTEM


  1. FUNCTION OF MAIN COMPONENTS


    1. The main components of the engine control system are as follows:

      Component Outline Quantity Function
      ECM VFOREST + VFOREST 1 Optimally controls the engine control system to suit the operating conditions of the engine in accordance with the signals provided by the sensors.
      Air Fuel Ratio Sensor (Sensor 1) Type with Heater (Planar Type) 1 Detects the oxygen concentration in the exhaust emissions by measuring the electromotive force which is generated in the sensor itself.
      Air Fuel Ratio Sensor (Sensor 2)*1 Type with Heater (Cup Type) 1
      Oxygen Sensor (Sensor 2)*2 Type with Heater (Cup Type) 1
      Intake Mass Air Flow Meter Sub-assembly Air Flow Meter Hot-wire Type 1 Uses a built-in hot-wire to directly detect the intake air mass.
      Intake Air Temperature Sensor Thermistor Type 1 Detects the intake air temperature.
      Engine Coolant Temperature Sensor Thermistor Type 1 Detects the engine coolant temperature.
      Fuel Pressure Sensor For Low Pressure Semiconductor Type 1 Detects the fuel pressure in the fuel delivery pipe.
      For High Pressure Semiconductor Type 1
      Crank Position Sensor [Rotor Teeth] Magnetic Resistance Element (MRE) Type [36 - 2] 1 Detects the engine speed and performs the cylinder identification.
      Camshaft Position Sensor [Rotor Teeth] Magnetic Resistance Element (MRE) Type [3] 2 Performs the cylinder identification.
      Throttle Position Sensor Non-contact Type 1 Detects the throttle valve opening angle.
      No. 1 Turbo Pressure Sensor Turbo Pressure Sensor Semiconductor Type 1 Detects the turbo pressure.
      Intake Air Temperature Sensor Thermistor Type 1 Detects the intake air temperature.
      No. 2 Turbo Pressure Sensor Semiconductor Type 1 Detects the turbo pressure.
      Accelerator Pedal Sensor Assembly Non-contact Type 1 Detects the amount of pedal effort applied to the accelerator pedal.
      Knock Control Sensor Built-in Piezoelectric Element Type (Flat Type) 1 Detects an occurrence of engine knocking indirectly from the vibration of the cylinder block caused by the occurrence of engine knocking.
      Oil Pressure Sender Gauge Assembly Semiconductor Type 1 Detects the engine oil pressure.
      Temperature Sensor Thermistor Type 1 Detects the engine oil temperature.
      Cam Timing Oil Control Solenoid Assembly Solenoid Type 1 Controls the intake camshaft (camshaft) phase to achieve the optimal valve timing by moving the oil control valve.
      Camshaft Timing Oil Control Valve Assembly Solenoid Type 1 Changes the oil passage to the VVT-i controller in response to signals from the ECM.
      Throttle Control Motor DC Motor 1 Regulates the opening of the throttle valve in accordance with the signals from the ECM.
      Fuel Injector Assembly For Port Injection 12-hole Type*2 4 This injector is an electromagnetically-operated nozzle which injects fuel in accordance with signals from the ECM.
      10-hole Type*1 4
      For Direct Injection High Pressure Single Slit Nozzle Type*2 4 This injector contains a high-pressure electromagnetically-operated nozzle used to inject fuel directly into the cylinder.
      6-hole Type*1 4
      Ignition Coil Assembly Type with Igniter 4 Incorporates an igniter and provides a high level of voltage necessary for ignition in accordance with signals from the ECM.
      Spark Plug Iridium-tipped Type 4 Sparks a high level of voltage from the ignition coil assembly inside the cylinder.
      Electric Water Pump Assembly Brushless Motor 1 Based on signals from the ECM, engine coolant is pressure-fed to the turbocharger sub-assembly and intercooler assembly.
      Oil Pressure Switching Valve Assembly Solenoid Type 1 Based on signals from the ECM, the supply of engine oil to the piston jet is controlled.
      Vacuum Regulating Valve Assembly Solenoid Type 1 Based on signals from the ECM, the wastegate valve is opened and closed.
      Air Bypass Valve Solenoid Type 1 Based on signals from the ECM, the air bypass valve is opened and closed.
      Pressure Discharge Valve Assembly Solenoid Type 1 Based on signals from the ECM, fuel pressure (low pressure) is controlled.

      *1: Models with gasoline particulate filter (GPF) system

      *2: Models without gasoline particulate filter (GPF) system

  2. SYSTEM CONTROL


    1. The engine control system has the following features:

      System Outline
      Direct Injection 4-stroke Gasoline Engine Superior Version with Turbo (D-4ST) This system comprehensively controls the D-4S and turbo pressure control.
      Direct Injection 4-stroke Gasoline Engine Superior Version Sequential Multiport Fuel Injection (D-4S SFI) System

      • This is an L-type SFI system. It directly detects the intake air mass with a hot-wire type intake mass air flow meter sub-assembly.

      • The D-4S SFI system is a fuel injection system which combines direct injection injectors and port injection injectors.

      • Based on signals from each sensor, the ECM controls the injection volume and timing of each type of injector (direct and port injection types) in accordance with the engine speed and engine load in order to optimize combustion conditions.
      Electronic Spark Advance (ESA)

      • Ignition timing is determined by the ECM based on signals from various sensors. The ECM corrects ignition timing in response to engine knocking.

      • This system selects the optimal ignition timing in accordance with the signals received from the sensors and sends ignition (IGT) signals to the igniters.
      Electronic Throttle Control System-intelligent (ETCS-i) Optimally controls the opening angle of the throttle valve in accordance with the accelerator pedal input and the engine and vehicle operating conditions.
      Variable Valve Timing-intelligent Wide (VVT-iW) Regulates operation of the intake camshaft to ensure an optimal valve timing in accordance with the engine condition.
      Variable Valve Timing-intelligent (VVT-i) Regulates operation of the exhaust camshaft to ensure an optimal valve timing in accordance with the engine condition.
      Cooling Fan Control

      • The cooling fan ECU steplessly controls the speed of the fans in accordance with the engine coolant temperature, vehicle speed, engine speed, and air conditioning operating conditions. As a result, the cooling performance is improved.

      • After the engine is stopped (the engine switch is off), the ECM may operate the cooling fan according to the driving conditions and engine condition.
      Fuel Pump Control (for Low Pressure)

      • Based on signals from the ECM, the fuel pump control ECU controls the fuel pump.

      • The fuel pump is stopped when any of the Supplemental Restraint System (SRS) airbags are deployed.
      Variable Fuel Pressure Control Controls the fuel pressure (low pressure) by controlling the pressure discharge valve assembly in accordance with the engine condition.
      Fuel Pump Control (for High Pressure) Regulates the fuel pressure within a range of 4 MPa to 18 MPa in accordance with driving conditions.
      Air Fuel Ratio Sensor Heater Control Maintains the temperature of the air fuel ratio sensor at an appropriate level to increase accuracy of detection of the oxygen concentration in the exhaust gas.
      Oxygen Sensor Heater Control Maintains the temperature of the oxygen sensor at an appropriate level to increase accuracy of detection of the oxygen concentration in the exhaust gas.
      Turbocharger Control

      • Controls the turbo pressure by opening and closing the wastegate valve in accordance with driving conditions.

      • Prevents the surge phenomenon*1 by opening and closing the air bypass valve in accordance with driving conditions.
      Electric Water Pump Control Controls the amount of engine coolant sent to the turbocharger sub-assembly and intercooler assembly in accordance with the engine condition.
      Piston Jet Control System Controls the piston jet engine oil injection in accordance with the engine condition.
      Drive Start Control System Even if the driver is in a hurry and abnormal accelerator pedal and shift operations are performed, vehicle speed and acceleration are restricted to improve the sense of security felt by the driver.
      Brake Override System The driving torque is restricted when both the accelerator and brake pedals are depressed. (For the Activation Conditions and Inspection Method, refer to the repair manual.)
      Evaporative Emission Control

      • The ECM controls the purge flow of the evaporative emission (HC) from the charcoal canister assembly in accordance with engine conditions.

      • Approximately 5 hours after the engine switch has been turned off, the ECM operates the canister pump module to detect any evaporative emission leakage occurring between the fuel tank assembly and the charcoal canister assembly through changes in the fuel tank assembly pressure.*2

      • For details, see the 8AR-FTS EMISSION CONTROL section.
      Engine Immobiliser Prohibits fuel delivery and ignition if an attempt is made to start the engine with an invalid key.
      Oil Maintenance Reminder System The oil maintenance information message is shown on the multi-information display according to the vehicle condition to inform the driver. For details, see the METER / GAUGE / DISPLAY section.
      Fail-safe When the ECM detects a malfunction, the ECM stops or controls the engine according to the data already stored in memory.
      Diagnosis When the ECM detects a malfunction, the ECM diagnoses and memorizes the failed section.

      Tech Tips

      *1: Surge phenomenon: This phenomenon is when the intake airflow reverses. As a result, an abnormal noise is easily generated during deceleration.

      *2: Models for Korea