Fuel-injection system

Fuel-injection system, method of supplying fuel to internal combustion engines. It has always been used in diesel engines, where fuel is sprayed into the cylinder; when the inlet valve or port closes, the high pressure developed as the piston moves up the cylinder ignites the fuel. In gasoline engines there is a separate fuel injection line for each cylinder. Fuel is injected into a port, not into the cylinder. Electronic or mechanical devices ensure that each cylinder receives the correct mixture of fuel and air for efficient combustion. A fuel-injection system thus replaces the carburetor in gasoline engines. First used on aircraft and racing car engines, since 1957 it has been used on some automobiles.

See also: Engine.