This fuel injection system used a high injection pressure under electronic control and a fuel delivery method known as a pilot injection that is electronically controlled by the electronic injection system via the injector (instead of being controlled by the injection pump as in previous direct injection engines).Pressure level is the basic parameter for optimising fuel consumption and exhaust fume levels.A pilot injection makes it possible to preheat the combustion chamber to avoid the pressure peak causd by rapid combustiojn and ensure smoother running.Injection pressure regulation is made possible by the constructional features of the system, which is equipped with separate pressure pump and injectors, both managed by a control unit. In this way, injection pressure is independent of engine rotation speed.The main features of the fuel feed system are as follows:- high injection pressure (up to 1350 bar);- injection pressure that can be modulated from 150 to 1350 bar under all engine operating conditions- introduction of fuel up to 100 mm³/cycle within a speed range of 100 to 6000 rpm;- precise injection control in terms of advance and duration;- a pilot injection before TDC managed on the basis of rpm and engine load that allows pressure drift in the combustion chamber to be reduced to lower noise levels.
COMPOSITION
The fuel system is divided into a low pressure circuit and a high pressure circuit.The low pressure circuit consists of:- an auxiliary pump submerged in the tank;- the fuel filter;- the fuel return manifold pipe;- the connecting pipes.The high pressure circuit consists of:- the pressure pump;- the single fuel manifold pipe;- the injectors;- the connecting pipes.
1 - Fuel tank2 - Submerged fuel assembly complete with level gauge control3 - Fuel filler pipe4 - Inertia switch5 - Fuel filter filter element6 - Water in fuel filter sensor7 - Pressure pump8 - High pressure pipes9 - Single fuel manifold pipe (rail)10 - Injectors11 - Pipe from injectors to fuel return manifold pipe12 - Return pipe from rail to fuel return manifold pipe13 - Fuel return manifold pipe14 - Fuel pressure regulator on pump15 - Fuel pressure sensor
