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The multi-injection system (engine SR20DE)

The position of individual elements of the fuel injection system and the ignition system in the engine compartment of the car with the engine SR20DE

1 - adsorber 2 - the valve of additional air 3 - injection valves 4 - fuel pressure regulator 5 - throttle position sensor 6 - the fuel filter 7 - switching valve, adjustable idle	8 - the coolant temperature sensor 9 - air regulator 10 - resistor 11 - transistor 12 - ignition coil 13 - crank angle sensor 14 - air flow meter

If you open the hood, you can see the ordinary for a modern car set of hoses, wires and other components which are or injection system, or to the ignition system. The illustration above shows a view of the engine compartment showing the location of the main elements of both systems. Let us briefly examine some of the elements. Crank angle sensor (13) is set in the ignition distributor is the main element of the two systems. The sensor monitors the engine speed and the position of the pistons, and sends a corresponding signal to the control unit for controlling the fuel injection, ignition and other functions. The sensor has a rotary drive and the current loop. The disc 360 has splines, each of which corresponds to one rotation of the crankshaft ?�, and 4 other slots that are 4 cylinders and are spaced 180 ?�. The current loop installed lighting and solar cells. When the rotor passes between the light and photocell splines on the disc interrupts the light signal transmitted from the LED to the photocell. Without going into details, we can say that in this case the pulses are generated which are transformed current circuit and is sent as signals to an electronic control unit. Last processes them and makes appropriate adjustments to the ignition and injection systems.

1. Air flow meter (14) is next to the air filter, and measures the amount of intake air. Measurement is as follows: an electronic control unit receives an electrical signal that corresponds to the heat released by the heating element, blowing flow of the intake air. When the intake air flowing into an intake conduit while blowing a heating element, the air receives the heat generated by this element. The amount of heat depends on the quantity of air. Since the temperature of the heating element is automatically adjusted to a certain value that is necessary to supply current to the heating element to maintain the cell temperature constant. Based on changes in the electrical control unit determines the amount of air.
2. Engine temperature sensor (8) for an oil filter is in the specified location on the illustration below. The sensor monitors the temperature of the coolant and as a signal transmits information to the electronic control unit. The sensor is equipped with a thermistor, responds to changes in temperature. Electrical resistance of the thermistor decreases with increasing temperature.

Position the coolant temperature sensor (1) near the oil filter (2).

3. Throttle position sensor (5) reacts to the movement of the gas pedal. It converts a throttle position signal and transmits it to the electronic control device. The control unit determines the position of the idle throttle when the unit receives a corresponding signal, and is, for example, stops the fuel supply.
4. Injection valves (3) have small switching valve. When the electronic device sends a signal to the valve injection, retracts the needle valve coil and fuel injected into the intake conduit. As long as fuel is injected is determined by the control unit.
5. The fuel pressure regulator (4) support in the constant pressure 3.0 bar. Since the quantity of fuel injected depends on the duration of the injection pressure must be maintained at a predetermined level.
6. Outgoing from the device control signal is supplied to the amplifier stage (11) which controls the primary ignition coil circuit. High voltage is removed from the secondary coil circuit. The ignition coil is not a standard type.
7. Air regulator (9) regulates the flow of air bypassing the throttle valve when the engine is cold or warm-up time on the fast idle. The controller responds to temperature and it changes depending on the cross section of the channel. The site (2) is a secondary air valve, which operates a pilot valve (7). These interdependent elements receive signals from the control unit and adjust the idle speed of the engine by a predetermined value. The illustration below shows how the switch module. At the specified location is idling adjustment screw.

Type of additional air valve and associated components

1 - a bolt of adjustment xx 2 - the valve of additional air 3 - switching valve

7. The speed sensor is installed in the speedometer and converts the speed impulses that are fed to the control unit. In order to maintain the idle speed when the engine is subjected to additional load while the servo control in the high pressure pipe steering an oil pressure sensor, which outputs a control signal to the unit load. It informs the additional air valve, the need to increase idle speed, depending on the size of the load.
8. In the cylinder block of the engine knock sensor is located. If the engine due to knock prone to vibration sensor is converted into a voltage signal that is supplied to the control unit.
9. The fuel filter (6) is located in a metal housing to withstand high fuel pressure. By the top and bottom of the filter is connected on one hose. The filter sits in a spring latch. Before you replace the filter (recommended every 40,000 km or every 2 years), it should reduce the fuel pressure in the system to avoid splashing of fuel. Use only the appropriate Specifications filter.
10. Adsorber with activated carbon (1) is used for the purposes described in Section systems reduce emissions for gasoline engines. All items related to the ignition system are described in Chapter electrical system of the engine.
11. The fuel pump located in the fuel tank. The control unit includes a fuel pump in a few seconds after the ignition is switched on, in order to facilitate starting the engine. When the control unit receives from crankshaft position sensor signal is "180", he knows that the motor rotates and turns on the pump. If the signal fails, the engine switches off and the pump is installed in such a mode in which the battery voltage is saved and secure. The control unit starts the pump via a separate relay.
12. On cars with a catalyst in the exhaust system installed lambda probe. It measures the oxygen content in the exhaust gas, and changes the ratio of fuel and air in accordance with this.

Work on the system

When carrying out any work on the system in which the fuel lines are disconnected, you must first reduce the fuel pressure. At the same time, proceed as follows:

PERFORMANCE ORDER

Open the fuse box cover and remove the fuse shown in the illustration. It's the fuel pump fuse. Now start the engine. After a while it will stall, as it will not receive fuel. Two or three times crank the starter to reduce all the pressure. Immediately insert the fuse in place. You can now disconnect all fuel hoses between the engine and the body. The position of the fuel pump fuse (1) in the fuse box. For all the others, especially the electrical work which require the knowledge necessary to observe the following precautions: Use only 12-volt battery. Never disconnect the battery cables with the engine running. Never disconnect cables injection valves with the engine running. Never push the injection valves are connected directly to the battery devices. Air flow meter is very sensitive and should be treated accordingly. It can not be disassembled. It also should not be washed with any liquid. Additional air valve can not be disassembled. Even small leaks in the system, place the air intake may affect the operation of the engine. The electronic control unit can not be repaired. When starting the engine do not squeeze the gas pedal. Do not increase the engine speed immediately after start-up and shutdown. If there is no fuel in the tank, do not turn the starter motor to start the engine, since the fuel pump must not operate without fuel. Always connect the cable connectors of the control unit as described. Misalignment can lead to shock and stress because of the damage to the ignition coil and the other elements. Keep the main wiring is at least 10 mm from the other cables in order to avoid exposure to external cabling. All cable harnesses must be dry. Always turn off the ignition and disconnect a cable of weight from the battery before loosen any connection.