Direct fuel injection

With direct fuel injection, fuel is injected directly into the combustion chamber. The fuel pump delivers fuel at a pressure of about 900 bar, and the fuel is injected in two stages.

The use of dual-channel fuel injectors makes it possible to make the initial injection of a small part of the fuel, as a result of which the combustion process of the fuel is improved, and the combustion process itself proceeds more smoothly. The amount of fuel injected is controlled by the electronic engine management system.

The amount of fuel injected is controlled by the control system based on information from the following sensors:

• accelerator pedal position sensor. The accelerator pedal position sensor provides information to the engine control device about the position of the accelerator pedal at the present time;
• engine crankshaft speed sensor;
• fuel injector needle movement sensor. Based on the information from this sensor, the moment of fuel injection is determined and the injection process is adjusted depending on the operating conditions and engine crankshaft speed;
• engine air pressure sensor (boost sensor);
• temperature sensor of the air entering the engine;
• coolant temperature sensor;
• diesel fuel temperature sensor;
• spool position potentiometer. Based on the information from this sensor, the actual amount of injected fuel is determined.

The air entering the engine in the intake ducts is twisted in a spiral, as a result of which the combustion process in the engine cylinders improves. It also makes it easier to start a cold engine, and the engine must be preheated at air temperatures below -10°C.


Before fuel enters the high pressure fuel pump, the fuel passes through the fuel filter, which also separates water from it, which must be drained periodically.

The fuel pump is driven by the engine crankshaft through a toothed belt. The internal moving parts of the fuel pump are lubricated with diesel fuel.

Warning: Do not allow diesel fuel to come into contact with the cooling system hoses. Hoses that have been exposed to diesel fuel for a long time must be replaced.

Warning: The diesel engine fuel system is particularly sensitive to contamination, so when working on the fuel system, be as clean as possible. Before disconnecting the fuel lines, thoroughly clean them of dirt.

Do not use compressed air to clean engine-mounted fuel system components.

Warning: When checking the operation of the fuel injectors, never put your hands or any part of your body under the jet of fuel coming out of the injector. The fuel exits the nozzle at high pressure and can enter the body through the skin.