Abstract: Engines fuelled with gaseous fuel stored in liquefied form comprise different strategies and controls for managing gaseous fuel compared to other systems, previously resulting in an ad hoc arrangements of controllers. An engine control apparatus comprises an internal combustion engine fuelled with a gaseous fuel stored in liquefied form and a control unit programmed with a fuel system module, for monitoring gaseous fuel pressure and actuating a fuel injection apparatus for introducing gaseous fuel into a combustion chamber, and a liquefied gaseous fuel module, for monitoring the quantity of liquefied gaseous fuel remaining in a storage vessel and controlling a pumping apparatus that pumps liquefied gaseous fuel from the storage vessel to a vaporizer. The fuel system control module and the liquefied gaseous fuel control module cooperate to introduce gaseous fuel in the combustion chamber at a predetermined pressure as a function of engine operating conditions.