Modern gasoline engines, especially Otto-cycle engines, continue to evolve rapidly, delivering greater fuel efficiency and higher specific power. In the 1970s, for example, a 1.5 L engine typically produced between 50 and 60 hp. Today, an engine of the same displacement can generate between 150 and 170 hp, primarily due to advances such as electronic engine management, direct injection, and turbocharging.

However, these engines are designed to operate under precise conditions, and their performance depends heavily on fuel quality and system cleanliness. Even when good-quality fuel is used, carbon deposits can gradually accumulate over time, leading to reduced engine efficiency, loss of performance, increased fuel consumption, rough operation, and higher maintenance requirements.

In Gasoline Direct Injection (GDI) engines, the fuel injector is positioned directly inside the combustion chamber rather than upstream of the intake valve. This design improves efficiency and power output, but it also makes the engine more sensitive to fuel quality. Because injectors operate under high pressure and temperature conditions, they are more vulnerable to deposit formation, carbon buildup, and clogging, which can negatively affect spray pattern, combustion quality, drivability, and fuel economy.