conventional spark - ignited gas engines with a mechanically controlled fuel feed valve have several disadvantages in terms of operation , expensive control , irregular combustion or unstable and unreliable operation , which in turn can lead to operational and mechanical problems . in order to eliminate these disadvantages it is suggested , according to the invention , that a controlled valve is installed in the fuel line upstream of the fuel feed valve so that in the fuel line between fuel feed valve and controlled valve a defined intermediate volume is created and gaseous fuel is fed via the controlled valve into the intermediate volume .