What are full group, semi-sequential, and full-sequential injection systems? What are the main differences between them? Working principle of single-point and multi-point injection systems …..
There are four types of injection vehicles: single point injection (SPI), mechanical, electromechanical (SPI), and multi-point injection (MPI). Multi-point injection vehicles can be divided into three groups: full group injection (two-channel sequential injector system), semi-sequential (2-channel sequential injector system), and full-sequential (4-channel system).
Multi-Point Injection Systems (MPI)
MPI systems contain one injector per cycle, and they are located near the intake valves.
The first sequential injection system was installed in 1995-96. These systems were controlled by the ECU (Electronic Control Unit), the electronic control unit that controls the vehicle’s fuel supply.
The ECU controlled injectors to inject the vehicle’s fuel into the cylinders. The first injector system was used in engines. It adjusted the amount of fuel to match the engine’s speed and applied it to all cylinders simultaneously. According to data from sensors, the injection relay would adjust the fuel amount. This type of injector system allows for simultaneous spraying and is called “Automotives”. “Full Group” .
Later, injectors began to be used in engines with injectors as a whole. Two sets of sensors controlled two cylinders, while the other set controlled the remaining cylinders. The 4 cylinder engine had the 1st and 4th injectors, and the 2nd & 3rd injectors. This system was known by the “Half Sequence” Oder “Two-Channel Sequential Injection” system.
In “Four Channel Sequential Injection” (Sequential Fuel System 4), injectors work independently. Each cylinder receives gasoline according its needs. The motor shaft controls the spraying time. Each injector is given a separate command by the petrol relay. Four wires are used to control the four injectors. This system is where the four gasoline injectors operate one by one. It was known as the “Sequential Injection System” .
Mechanical Injection Systems
Gasoline is injected mechanically in vehicles that have mechanical injection. The volume of gasoline is determined by how much air is sucked into the cylinders.
Electromechanical Injection Systems
Electromechanical injection vehicles work in the same way as mechanical injection. An actuator controls the amount and type of gasoline that is injected into the cylinders. This is the K-Jetronic gasoline controller.
K-Jetronic Systems:
The amount of gasoline to inject is determined by the airflow being drawn. The gasoline pump is used to return the gasoline at low pressure through gas operation.
Single Point Injection Systems (SPI)
Vehicles with single-point injection (SPI) have gasoline injected into the cylinders based on the revolution of engine shaft (2 complete revolutions). The command from the fuel relay adjusts the amount of gasoline. Based on information from sensors such as Temperature, Pressure, and Temperature, the injection relay transmits a command to adjust the amount of gasoline to injectors. in the engine.
