SFI SYSTEM CONTROL ENGINE CONTROL

  1. FUNCTION OF MAIN COMPONENTS

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

      Component

      Quantity

      Function

      ECM

      1

      Optimally controls the sequential multiport fuel injection, electronic spark advance, and electronic throttle control system to suit the operating conditions of the engine in accordance with the signals provided by the sensors.

      Crank Position Sensor

      1

      Detects the engine speed and performs cylinder identification.

      Camshaft Position Sensor

      2

      Performs cylinder identification.

      Knock Control Sensor

      1

      Monitors the combustion of the fuel/air mixture.

      Vacuum Sensor Assembly

      1

      Uses built-in semiconductors to detect the intake manifold pressure.

      Intake Air Temperature Sensor

      1

      • Is built into the vacuum sensor assembly.

      • Detects the intake air temperature by means of an internal resistor.

      Throttle Body with Motor Assembly

      1

      • Regulates the quantity of air admitted in the cylinders.

      • Creates a vacuum in the air inlet necessary for the intake of petrol vapors originating from the canister, the intake of recirculated oil vapors, and for the braking assistance.

      Heated Oxygen Sensor

      2

      Detects the oxygen concentration in the exhaust gas by measuring the electromotive force which is generated in the sensor itself.

      Accelerator Pedal Sensor Assembly

      1

      Detects the amount of pedal effort applied to the accelerator pedal.

      Engine Coolant Temperature Sensor

      1

      Detects the water temperature by means of an internal thermistor.

      Fuel Injector Assembly

      3

      Is an electromagnetically-operated solenoid with a nozzle which injects fuel in accordance with signals from the ECM.

  2. SYSTEM CONTROL

    1. The engine control system of the 1PP engine has the following systems.

      Components

      Function

      Sequential Multiport Fuel Injection

      • The D-type sequential multiport fuel injection system calculates the intake air volume based on the intake manifold pressure signal received from the vacuum sensor assembly and the engine speed.

      • An independent injection system in which fuel is injected once into each cylinder for every 2 revolutions of the crankshaft is used.

      Electronic Spark Advance

      • 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 the ignition (IGT) signal to the igniter.

      Electronic Throttle Control System

      Optimally controls the throttle valve opening in accordance with the accelerator pedal opening angle, the throttle valve opening control request from the ECM and the engine and vehicle operating conditions.

      Dual Variable Valve Timing

      Controls the intake and exhaust camshafts to ensure optimal valve timing in accordance with the engine operating conditions.

      Fuel Pump Control

      Fuel pump operation is controlled by signals from the ECM. The fuel pump is stopped when any of the airbags is deployed in a collision.

      Cooling Fan Control

      The ECM steplessly controls the speed of the fan via the cooling fan ECU in accordance with the engine coolant temperature, vehicle speed, engine speed, and air conditioning conditions*1. As a result, good cooling performance has been achieved.

      Starter Control (Cranking Hold Function)*2

      After the engine switch is pushed, continuously operates the starter until the engine starts.

      Heated Oxygen Sensor Heater Control

      Maintains the temperature of the heated oxygen sensor at an appropriate level to increase the ability of each sensor to accurately detect the oxygen concentration in the exhaust gas.

      Engine Immobiliser

      Prohibits fuel delivery and ignition if an attempt is made to start the engine with an invalid key.

      Air Conditioning Cut-off Control*1

      By turning the compressor with pulley assembly on or off in accordance with the engine operating conditions, drivability is maintained.

      *1: Models with air conditioning system

      *2: Models with entry and start system

  3. FAIL-SAFE

    1. When a malfunction of any of the sensors is detected, there is a possibility of an engine or other malfunction occurring if the ECM were to continue normal control. To prevent such a problem, the fail-safe function of the ECM either relies on data stored in memory to allow the engine control system to continue operating, or stops the engine if a hazard is anticipated. For details, refer to the Repair Manual.

  4. DIAGNOSIS

    1. When the ECM detects a malfunction, the ECM records information related to the malfunction. Furthermore, the Malfunction Indicator Lamp (MIL) in the combination meter assembly illuminates to inform the driver.

    2. The ECM also stores Diagnostic Trouble Codes (DTCs) for malfunctions it has detected. The DTCs can be accessed by using the Global TechStream (GTS).

    3. For details, refer to the Repair Manual.