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Two-stroke gasoline engines are known to benefit from using in-cylinder fuel injection which improves their ability to meet the strict fuel economy and exhaust emissions requirements. A conventional method of in-cylinder fuel injection involves application of plunger-type positive displacement pumps. Two-stroke engines are usually smaller and lighter than their 4-stroke counterparts of equal power and need a pump that should also be small and light and, preferably, simple in construction. Because a 2-stroke engine fires every crankshaft revolution, its fuel injection pump must run at crankshaft speed (twice the speed of a 4-stroke engine pump). An electronically controlled fuel injection system has been designed to satisfy the needs of a small automotive 2-stroke engine capable of running at speeds of up to 6000 rpm.

A typical pattern of vehicle driving includes a series of frequent accelerations and decelerations. Fuel energy spent to accelerate the vehicle is later wasted during deceleration, when kinetic energy is converted into heat in friction brakes. New thermodynamic cycles have been conceived for automobile engines to capture the energy of braking in the form of compressed air, and reuse this energy during acceleration at a later time. They are applicable to all types of automotive engines. Each four-stroke cycle includes two power strokes, one with compressed air and a second one with combustion gas. It is also possible to switch the engine operation from a four-stroke to a two-stroke cycle during acceleration, which allows a reduction in engine displacement.