A fuel injector is provided. The fuel injector includes a sleeve having a first end proximate an outlet; a piston slidingly received in the sleeve, the piston having a first end proximate the outlet; a pumping chamber at least partially defined by the sleeve between the first end of the piston and the outlet; and a normally-open inlet valve through which fuel passes to enter the pumping chamber.

Disclosed are example embodiments of an electronic fuel injection device. In one example embodiment, the electronic fuel injection device includes: a yoke having an inner chamber; an armature and a plunger slidably disposed inside the inner chamber of the yoke; a cylindrical bobbin configured to receive the yoke; an electromagnetic coil disposed around an outside surface of the cylindrical bobbin; and a fuel return path formed between an outer surface of the yoke and an inner surface of the cylindrical bobbin. The inner surface of the cylindrical bobbin comprises surface cooling features, including channels or protrusions, configured to remove heat from the cylindrical bobbin.

A fuel injector is provided. The fuel injector includes a sleeve having a first end proximate an outlet; a piston slidingly received in the sleeve, the piston having a first end proximate the outlet; a pumping chamber at least partially defined by the sleeve between the first end of the piston and the outlet; and a normally-open inlet valve through which fuel passes to enter the pumping chamber.

A fuel injector is provided. The fuel injector includes a sleeve having a first end proximate an outlet; a piston slidingly received in the sleeve, the piston having a first end proximate the outlet; a pumping chamber at least partially defined by the sleeve between the first end of the piston and the outlet; and a normally-open inlet valve through which fuel passes to enter the pumping chamber.

A fuel injector is provided. The fuel injector includes a sleeve having a first end proximate an outlet; a piston slidingly received in the sleeve, the piston having a first end proximate the outlet; a pumping chamber at least partially defined by the sleeve between the first end of the piston and the outlet; and a normally-open inlet valve through which fuel passes to enter the pumping chamber.