What does ECU stand for in relation to fuel injection systems?

In relation to fuel injection systems, ECU stands for Engine Control Unit. The Engine Control Unit is a critical component in modern vehicles that manages the engine's performance by controlling various functions, including the fuel injection process. It utilizes input from various sensors to optimize fuel delivery based on the engine's needs, contributing to efficiency and performance. The ECU adjusts timing, air-fuel mixture, and other factors to ensure the engine runs smoothly and according to emissions regulations.

The other options refer to concepts that either do not exist as specific automotive technologies or do not accurately describe the role of the ECU in fuel injection systems. The Electric Control Unit and Emission Control Unit are not standard terms used in this specific context, and while the term "Efficient Control Unit" sounds plausible, it is not the accepted terminology in the industry. Thus, defining ECU as Engine Control Unit aligns with its widely recognized function in the management of fuel injection and engine performance.