Massachusetts Hoisting License Practice Test

What is the primary function of fuel injectors in a machine?

1. Mix air and fuel for combustion

2. Deliver fuel under pressure to the combustion chamber

3. Control the exhaust emissions

4. Regulate engine temperature

The correct answer is: Deliver fuel under pressure to the combustion chamber

The primary function of fuel injectors is to deliver fuel under pressure to the combustion chamber. This process is crucial in modern engines as it ensures that the optimal amount of fuel is precisely injected into the combustion chamber at the right time, allowing for efficient combustion. Fuel injectors atomize the fuel, creating a fine mist, which mixes with air to facilitate a more efficient burn. The ability to control the delivery of fuel under pressure is what distinguishes fuel injection systems from carbureted systems. By ensuring that the fuel is delivered in a precise manner, the fuel injectors help to optimize engine performance, fuel economy, and reduce emissions. Options related to mixing air and fuel or controlling exhaust emissions are functions that can be influenced by the operation of fuel injectors, but they are not the primary function. Similarly, regulating engine temperature is handled by distinct components such as the cooling system, rather than the fuel injectors themselves.