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Brief description

Brief description

Overview

Important

Be very thorough in terms of cleanliness when working in the fuel system. Malfunctions can also occur due to very small dirt particles. Prevent dirt from entering the fuel system by cleaning the hoses and plugging the pipes and lines upon removal. Store the components so that contaminants cannot enter.




• Fuel tank

• Feed pump integrated in fuel tank

• Fuel lines

• Fuel filter

• High-pressure pump

• Fuel control valve

• Fuel rail/reservoir

• Fuel pressure sensor

• High pressure pipe

• Injectors

• Return fuel hoses/pipes

• Return fuel tank


Description

The fuel system is of the type "common rail" direct injection. The fuel tank, which has a 58-litre capacity, contains a feed pump that sends fuel to the high pressure pump via a fuel filter. Feed pump pressure is 4 bar. The high pressure pump generates a pressure of 160 MPa (1600 bar) depending on the operating conditions. This ensure excellent atomisation of the injected fuel. The pump supplies a fuel rail which also serves as a reservoir.

A steel pipe runs from the fuel rail to each fuel injector. The injectors have seven jets. Two valves and one pressure sensor are used to regulate injection pressure. ECM regulates the timing and duration of the injection. In order to optimise injection, ECM injects fuel up to five times per power stroke. This is divided into


a. Pilot injection (1 injection)

b. Main injection (3 injections)

c. Regeneration injection (1 injection).


To give you an idea of the precision required during the injection procedure - the maximum duration of an injection is 1.1 millisecond (1.1 thousandths of a second).