https://docs.emtronaustralia.com.au/engine-management/reference/closed-loop-pid/index.htmlThe function “Closed Loop” is defined as a control system’s ability to react automatically based on a form of feedback (position, calculated value, frequency, etc). This is usually dependent on some sort of PID strategy. The Emtron ECU has closed loop controls for many Functions throughout the ECU. Common functions that rely on closed loop are: Closed Loop Lambda Control Idle speed control Idle Ignition Control VVT Cam control DBW ControlHugoen-us