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An electronic control system supervises and governs all engine parameters to optimise performance and fuel consumption by means of a real-time response to different operation conditions. Diesel engines are equipped with a COMMON RAIL type injection system. This features the use of an electronically controlled high injection pressure. The supply of fuel, known as the pilot injection, is optimised by the electronic control unit by means of the injector, rather than being managed by the pump. In this 4 valve per cylinder version, the Common Rail injection system uses the "MultiJet II" technology. In the previous MultiJet versions, the injector - capable of carrying out 5 consecutive injections during the same combustion cycle - was based on a hydraulic servo valve with unbalanced shutter, which required reduced sealing diameters and longer travels. In the new MultiJet II injection system, the injector shutter is hydraulically balanced resulting in greater sealing diameters and reduced shutter travels. Thanks to this new servo valve, the quantity of fuel injected in the combustion chamber can be controlled more precisely and quickly. Up to 8 consecutive injections can be managed with very precise measurement. This new injection mode ensures considerable advantages in terms of reduction of noise, fuel consumption and emissions. The throttle body is also controlled electronically by the control unit: the throttle opening is calculated in accordance with a specific logic inside the engine management control unit. Depending on the signals received from numerous sensors, the control unit manages the injectors connected to it, handling the following systems:
To comply with the latest emissions control regulations (EURO 5), the most recent electronic on-board management version is used, comprising new components (injectors, pressure regulator and high pressure pump, digital flow meter) and the adoption of an oxygen sensor. The oxygen sensor improves the air/fuel mixture in the combustion chamber regulating the flow of air: with the throttle open the power supply is at a maximum; closing the throttle gradually reduces the load, the engine rpm and also the emissions. In addition, the new EGR module fitted on this engine makes it possible to choose whether to cool the exhaust gases or exclude the cooling process by means of a by-pass. This operation, managed entirely by the engine management control unit, makes it possible to ensure optimum operation of the EGR in terms of nitrogen oxide reduction without adversely affecting hydrocarbon (HC) and carbon monoxide (CO) emissions. In addition to the oxygen sensor a DPF (Diesel Particulate Filter) is used: it is a mechanical filter, inserted in the exhaust pipes, which traps the carbon particles present in the Diesel engine exhaust gas. The filter makes it possible to almost totally eliminate the emission of carbon particles in line with current legislation. See E5070 PARTICLE FILTER SYSTEM Thanks to the electronic management described above, this engine carries out a continuous check according to the EOBD system (European On Board Diagnosis): this system allows continuous diagnosis of emission-related car components and notifies the driver if any of the components should deteriorate by turning on a warning light in the instrument panel. The aim of the system is to:
For more details, See descriptions 1060 DIESEL INJECTION FUEL SYSTEM The system is also controlled by dedicated relays in the engine compartment junction control unit. Lines supplying the control unit and various system components (sensors and actuators) are protected by dedicated fuses that are also located inside the engine compartment junction unit. |