https://docs.emtronaustralia.com.au/engine-management/tuning/fuel/acceleration-fuel-compensation/index.htmlDuring rapid changes in throttle position and engine load, fuel delivery does not immediately track the change in airflow. This is due to a portion of the injected fuel temporarily adhering to the intake port walls and intake valves as a liquid film before it evaporates and is drawn into the combustion chamber. When airflow increases rapidly, additional fuel is temporarily required to establish the larger fuel film while maintaining the correct air-fuel ratio. Without this compensation, the engine will momentarily operate lean, resulting in hesitation, poor throttle response or engine stumble.Hugoen-us