What is the primary function of a fuel injector in an engine?

• A. It ignites the fuel-air mixture in the combustion chamber
• B. It sprays a fine mist of fuel into the intake manifold or combustion chamber
• C. It filters out impurities from the fuel supply
• D. It maintains the engine oil pressure

Answer: (B)

The primary function of a fuel injector is to spray a fine mist of fuel into the intake manifold or combustion chamber. This precise delivery of fuel is crucial for the combustion process in internal combustion engines. By atomizing the fuel, the injector ensures that it mixes thoroughly with the air, which enhances combustion efficiency and power output.

Fuel injectors operate under high pressure, allowing them to create a fine mist rather than large droplets of fuel. This mist enables a more even and complete burn of the fuel, leading to better engine performance, improved fuel efficiency, and reduced emissions.

Understanding this function highlights the importance of fuel injection systems in modern engines, which have largely replaced older carbureted systems to meet stringent performance and emissions standards. Components such as ignition systems and oil pumps have different roles and do not pertain specifically to the spray function of fuel injectors, which is why they do not serve as correct answers in this context.