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Considering the world-wide market for GDI engines, the introduction of tighter polluting emission legislation, additional costs, vehicle fuel economy and pollutants reduction become substantial drivers. Focusing on particulate reduction, direct injection gasoline engines require advanced combustion strategies. The main levers used are injection splitting in order to reduce wall impingement (due to lower penetration) and higher rail pressure level to reduce droplet size. To reach this target it is necessary to improve precision in term of injected quantity in the small quantity region with high fuel rail pressure and during the actuation of multiple injections. As a consequence of the requirements of high quantities at full load, known GDI solenoid injectors show an unacceptable spread in terms of small injected quantity when the energizing time is small such that the injector works in the ballistic zone. Following these premises an electronic approach is needed.

Engines using compressed natural gas or liquefied petroleum gas are commonly equipped with control systems which are not yet able to completely monitor the gas supply line status. With a particular regard to safety but paying attention even to driving comfort and finally to polluting emissions reduction, two aspects in particular have been taken into account: the first one is the need to detect as soon as possible (and to react consequently) the presence of a problem occurring inside gas supply line (leakages and blocked-valves etcetera); the second one is the ability to detect an unsafe re-fuel operation, done with inserted ignition key, in order to switch off at least as more auxiliary loads as possible. The danger from such a manoeuvre may be identified in the high probability of an eventual electrostatic discharge and/or in the risk that the vehicle may be accidentally moved during the refilling operation.