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printable version
The functioning of the control system and injection petrol engine
Location of components in the engine compartment models C240 and C320
| 1 - Knock Sensor (KS) 1 (right engine) 2 - Knock Sensor (KS) 2 (left on the engine) 3 - The throttle position sensor (TPS) | 4 - Vacuum transmitter EGR 5 - valve switch configuration of the inlet pipeline 6 - The temperature sensor / quality / level of oil |
Fuel is sucked from the fuel tank electric fuel pump and is supplied through the fuel filter to the fuel distribution manifold. The pressure regulator maintains the pressure in the fuel system, equal to 3.2 - 3.6 atm. Through Power fuel injector pulse is injected into the intake pipe, located directly in front of the intake valves of the engine. The engine control unit produces a consistent control of injectors according to the order of ignition, adjusts the injection time and thus the amount of fuel injected.
The air required for the formation of fuel mixture sucked in the engine through the air filter and flows through the throttle valve and the intake pipe to the intake valves. The amount of intake air is regulated by a throttle valve, which moves stepper motor controlled by the engine control unit. At compressor engine intake air compressed by the compressor, driven by belt transmission from. The compressed air is cooled in the charge air cooler and is supplied to the engine to form a fuel mixture.
The volume of intake air is determined by the measure of the amount of air. The meter is located in the intake air passage. The meter body is thin, electrically heated sensor plate cooled by passing a stream of intake air. Electric current heater plate, a control system is regulated so as to maintain the temperature of the plate constant. If, for example, the amount of intake air increases, the temperature of the heater plate begins to decline. The magnitude of the electric current immediately increases to maintain the temperature of the plate constant. Fluctuations in the electric current of the plate indicates the engine control unit on its load status, which allows you to properly determine the amount of fuel injected.
The engine control unit is located in the electronics box, the left side, about the brake fluid reservoir or directly on the engine. The control unit determines the optimum ignition timing, injection timing and quantity of fuel injected. Thus there is a coordination of the work of the control unit with other vehicle systems, such as transmission control or anti-theft system.
The information from the other sensors and the control voltage is supplied to the executive bodies, provide optimum engine performance in any situation. If some of the sensors fail, the control unit switches to the emergency program in order to avoid possible damage to the engine and to drive further. In this case, the motor runs unevenly and with an increase in the gas tends to stop.
Sensors and executive bodies of the injection system
The crankshaft position sensor is screwed into the cylinder block at the flywheel. It transmits information to the control unit of the engine speed and TDC position of first cylinder.
Camshaft sensor is located on the end of the cylinder head cover. He, along with the crankshaft position sensor sends information to the control unit of the TDC of first cylinder. It serves to synchronize the ignition timing and ignition sequence.
Throttle actuator comprises a motor and two potentiometers. It regulates the throttle position. This ensures a stable idle speed, regardless of the connection of additional consumers, such as the power steering or air conditioning compressor.
Throttle potentiometer located in the throttle actuator control unit and communicates information about the current angle position of the throttle. The second potentiometer informs the control unit about the base value and generates a replacement signal in case of failure of the throttle potentiometer.
Gas pedal sensor is the area of the driver's feet directly on the axis of the gas pedal. It tells the control unit information about the position of the pedal. For reasons of safety pedal sensor taken from an additional signal, as well as from the throttle potentiometer.
Coolant temperature sensor located in the thermostat housing. It is a resistor with a negative temperature coefficient of resistance decreases with increasing temperature.
Intake air temperature sensor is also an NTC-resistor.
The ventilation system consists of the fuel tank and the canister solenoid valve. The adsorber accumulates fuel vapor generated by heating fuel. When the engine is sucked from the adsorber pair and fed into the engine combustion chamber.
Lambda sensors (oxygen sensors) measuring the oxygen content in the exhaust gases before and after the catalytic converter and transmitting appropriate signals to the engine control unit. One lambda sensor located in front of and one downstream of the catalytic converter.
Knock sensor vv?�rnut in the engine block near the guide tube. It prevents the emergence of a dangerous impact of the combustion of the fuel mixture. Due to this ignition timing can keep knocking limit, which ensures efficient use of energy fuel combustion and thus reduces fuel consumption.
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