What is the difference between direct and port fuel injection?

The correct choice highlights the fundamental difference in how fuel is delivered to the engine in direct and port fuel injection systems. In direct injection, fuel is injected directly into the combustion chamber under high pressure. This method allows for more precise control over the fuel-air mixture, leading to improved efficiency and performance. It can enhance combustion, reduce emissions, and provide better throttle response.

On the other hand, port fuel injection operates by injecting fuel into the intake manifold before it enters the combustion chamber. This allows the fuel to mix with the incoming air, ensuring thorough mixing before combustion begins. Port injection is comparatively simpler and allows for better fuel atomization at lower engine loads, contributing to improved fuel economy in certain operating conditions.

This distinction between the two injection types is crucial in understanding how modern gasoline engines can be optimized for performance, fuel economy, and emissions control.