A method for controlling a fuel system of a multiple injector engine provides a primary fuel injector and a secondary fuel injector which are both connected in fluid communication with an air stream flowing to a combustion chamber of the engine. Based on the total magnitude of fuel required to be injected into the air stream and as a function of the engine speed and percent load of the engine, first and second shares of the total magnitude of fuel are determined for the primary and secondary fuel injectors. The primary and secondary fuel injectors are then caused to inject their respective shares of the total fuel magnitude into the air stream, with the primary and secondary shares being determined as a function of engine speed and percent load of the engine.

An air assist fuel injector having an armature and a solenoid for actuating the armature. The armature includes a conduit having a conical portion for delivering liquid fuel and gas to a poppet of the air assist fuel injector. The conduit includes an inlet for receiving the liquid fuel and gas from a cap of the air assist fuel injector. The cap includes a number of channels for delivering the liquid fuel and gas, and the outlets of the channels are located radially inward of the periphery of the inlet to the armature conduit. The armature also includes a flow path located between an area upstream of the inlet to the armature and an area downstream of the armature. The flow path may include one or more recesses in the armature or one or more recesses in an armature guide of the air assist fuel injector.

A first air assist fuel injector configured for operation with a two stroke engine and a second air assist fuel injector configured for operation with a four stroke engine. The first air assist fuel injector and the second air assist fuel injector share one or more common items, such as a solenoid coil assembly and/or an armature, even though the air assist fuel injectors are configured for different applications.

A first air assist fuel injector configured for operation with a two stroke engine and a second air assist fuel injector configured for operation with a four stroke engine. The first air assist fuel injector and the second air assist fuel injector share one or more common items, such as a solenoid coil assembly and/or an armature, even though the air assist fuel injectors are configured for different applications.

A sealing arrangement for an air assist fuel injector having an interface cap. The sealing arrangement includes a sleeve sealingly attached to a leg of the air assist fuel injector and that receives at least a portion of the interface cap. A seal member abuts the sleeve to seal a solenoid from liquid fuel and gas and to seal an interface between the air assist fuel injector and a rail when the air assist fuel injector is received by the rail.