Red Seal Heavy Duty Equipment Technician Practice Exam

What is the purpose of a fuel injector in a diesel engine?

1. To compress air before combustion

2. To atomize and deliver fuel into the engine’s combustion chamber

3. To manage the engine’s RPM

4. To release excess pressure from the system

The correct answer is: To atomize and deliver fuel into the engine’s combustion chamber

The role of a fuel injector in a diesel engine is crucial for ensuring optimal engine performance and efficiency. Its primary purpose is to atomize and deliver fuel into the combustion chamber, where it can mix with air and combust effectively. This process is essential for the engine's operation, as the atomization of fuel allows for a finer mist, which promotes better combustion and energy extraction from the fuel. Unlike other components that may deal with aspects like air compression, engine speed management, or pressure regulation, the fuel injector specifically focuses on the precision delivery of fuel. This atomization is vital because it helps create a uniform mixture with air, leading to a more complete and efficient combustion process. Proper functioning of the fuel injector directly impacts power output, fuel economy, and emissions, which are critical factors in the performance of a diesel engine.