A fuel delivery system may be utilized in an internal combustion engine or a generator engine. The fuel delivery system includes a fuel injector and a venturi. The venturi provides a force for delivering the fuel into the manifold of the engine, and the fuel injector provides metering to control the amount of fuel delivered into the manifold of the engine. In one example, the fuel delivery system includes a first chamber configured to enclose a gaseous fuel, a second chamber configured to direct a flow of air through the venturi, and a plunger. The plunger is controlled to selectively connect and disconnect the first chamber and the second chamber to control the flow of the gaseous fuel into the second chamber under a differential pressure of the venturi.