The embodiment of the injector system shown in FIGS. 4 to 6 and described above provides a great deal of control over the operation of the injector, including control over the timing of the start and end of injection, the rate of injection, idle speed, and even variation in rate of injection within a single injection cycle. The greater degree of control that is possible makes the injector system particularly suitable for direct fired internal combustion engines.

The construction and arrangement of the injectors and associated controllers illustrated and described with reference to the drawings enables accurate and repeatable control of the point of commencement of the injection, accurate and repeatable control of the charge of liquid which is injected during each injection cycle, and accurate and repeatable point of termination of the injection. The three stage positive termination of injection makes the injector suitable for high speed two stroke engines.