Theengine controlunitcan be debugged by PC or Handheld debugger. This ECU is fit to Euro and Euro engines and vehicles with 3 to 8 cylinders. When fuling CNG,the ECU of sequential injection system will get the time of fuel injection in order to calculate how to control the opening time of injector.Engine system is mainly based on ECU to work. ECU control system can provide energy which will be equal to gasoline status in the same operation conditions to compensate the difference between those two.