In at least some implementations, a throttle body assembly includes a body that has multiple throttle bores, multiple throttle valve heads received one in each of the throttle bores, at least one throttle valve shaft to which the throttle valve heads are coupled, and at least one of a fuel metering valve and a vapor separator carried by the body.

A method for deposit mitigation in a gaseous fuel injector that introduces a gaseous fuel through a gaseous fuel orifice directly into a combustion chamber of an internal combustion engine includes at least one of a) reducing the ago length of the gaseous fuel orifice by substantially between 10% to 50% of a previous length of a previous gaseous fuel orifice showing deposit accumulation above a predetermined threshold; b) providing the gaseous fuel orifice with an inwardly and substantially linearly tapering profile; c) determining deposit mitigation is needed; and performing at least one of the following deposit mitigation techniques i) increasing gaseous fuel injection pressure wherein deposit accumulation is reduced during fuel injection; and ii) decreasing gaseous fuel temperature wherein a rate of deposit accumulation is reduced; and d) injecting compressed air through the gaseous fuel orifice during shutdown of the internal combustion engine; whereby torque loss in the internal combustion engine due to deposit accumulation in the gaseous fuel orifice is reduced below a predetermined value.

In at least some implementations, a charge forming device includes a body having a main bore, a fuel metering assembly including a diaphragm that defines at least part of a fuel chamber from which fuel is provided to the main bore and a reference chamber separate from the fuel chamber, a passage communicated with a subatmospheric pressure source and with the reference chamber, and an electrically actuated valve having an open position and a closed position, and wherein the valve at least substantially prevents communication of the pressure source with the reference chamber when the valve is in the closed position and permits communication of the pressure source with the reference chamber when the valve is in the open position to vary the rate of fuel flow from the fuel chamber.

In at least some implementations, a throttle body assembly includes a body that has multiple throttle bores, multiple throttle valve heads received one in each of the throttle bores, at least one throttle valve shaft to which the throttle valve heads are coupled, and at least one of a fuel metering valve and a vapor separator carried by the body.

A carburetor may have a fuel metering assembly with a metering valve and a metering diaphragm sealed to a body of the carburetor to at least partially define a metering chamber with a portion of the metering diaphragm movable relative to the body to actuate a fuel metering valve. The diaphragm may include a continuous layer, a discontinuous layer, and an intermediate layer received at least partially between the continuous and discontinuous layers and at least partially inhibiting direct contact between the continuous and discontinuous layers. The continuous and discontinuous layers may be different polymer materials and the intermediate layer may be a polymer different than that of the discontinuous layer. The intermediate layer may include voids, segments, or a wire form.

A carburetor may have a fuel metering assembly with a metering valve and a metering diaphragm sealed to a body of the carburetor to at least partially define a metering chamber with a portion of the metering diaphragm movable relative to the body to actuate a fuel metering valve. The diaphragm may include a continuous layer, a discontinuous layer, and an intermediate layer received at least partially between the continuous and discontinuous layers and at least partially inhibiting direct contact between the continuous and discontinuous layers. The continuous and discontinuous layers may be different polymer materials and the intermediate layer may be a polymer different than that of the discontinuous layer. The intermediate layer may include voids, segments, or a wire form.

The invention concerns a method for controlling the fuel supply to an internal combustion engine at start-up. The fuel supply system can be set in at least two start modes, a lean mode and a rich mode, and the selection of mode is based on an evaluation of a previous start attempt or successful run. The invention also concerns a carburetor (10) having a fuel supply system including a main fuel path (13) with an actively controlled fuel valve (26) and an idling fuel path (14) branching off from the main fuel path (13) downstream of the valve (26). The fuel supply system further includes a start fuel line (23, 423) starting upstream (FIG. 1) or downstream (FIG. 4) of the fuel valve (26) and ending in at least one start fuel outlet near and downstream of a choke valve.

To improve responsiveness of fuel supply control, a rotary carburetor 100 has a nozzle 8 including a fuel discharge port 8a and a needle 10 disposed coaxially with the nozzle 8 and disposed with a portion inserted into the nozzle 8. The needle 10 can be displaced relative to the nozzle 8 to change an effective area of the fuel discharge port 8a. The rotary carburetor 100 has an electric motor 14 for displacing the needle 10 along an axis, and a drive mechanism component 12 interposed between the electric motor 14 and the needle 10 and converting a rotational movement of the electric motor into a linear movement.

An electronic device for the ignition system of an engine, which may incorporate circuitry for voltage amplification via transformer action, while also containing circuitry for sensing operational parameters, circuitry for calculation of derived values from the sensed data or operational parameters, circuitry for storage of the data and derived values, circuitry for engine system control, and circuitry for the wireless communication of data and derived values.

An electronic device for the ignition system of an engine, which may incorporate circuitry for voltage amplification via transformer action, while also containing circuitry for sensing operational parameters, circuitry for calculation of derived values from the sensed data or operational parameters, circuitry for storage of the data and derived values, circuitry for engine system control, and circuitry for the wireless communication of data and derived values.