Abstract: An electro-magnetically operated valve for control of pressurized fluid including a coil bobbin disposed within a housing, having a plunger subassembly moveably mounted in said housing having a fixed valve seat at one end and a magnet mounted at the opposite end and including a flow passage extending there between, whereby the plunger is moveable responsive to an electronic coil mounted in the coil bobbin between an open position wherein the valve body member is in spaced relationship with the valve seat permitting flow of pressurized fluid, and a closed position whereby the valve body member is seated against the valve seat, said valve being connected to sensor apparatus for sensing phase relations of a piston of a pump operationally connected to a switch apparatus for forming a magnetic circuit including the electro-magnetic coil such that the valve is operated by positively controlling the opening the opening and closing of the valve by passing a current through the coil.