ECUs are an integral part of modern world cars. It controls and governs the various functioning elements of the vehicle such as controlling throttle valve, intake and exhaust valves, firing, rate of combustion etc. They are costly and are complicated to install and configure. So an electronically controlled ignition system is designed on Arduino Uno based microcontroller is designed. It is configured with all the inputs from various sensors sources such as throttle position sensor, pedal input, fuel richness sensor etc. These inputs are taken in real time and hence are fed to the board. Outputs such as the spark plug, transmission and fuel injection are the main controlling elements of the ECU. The main objective is to control or vary the rate of combustion as per requirement. It allows multiple performance modes by varying the throttle valve and ignition timing with respect to time. To improve the ignition efficiency for the DC capacitor discharge ignition (CDI) system, a spark frequency and duration; programmable ignition technique is adopted. The Arduino Uno microcontroller is employed to read the crankshaft speed signal through a Hall-effect sensor. Based on this input, the microcontroller controls the frequency of the firing. The proposed low cost ignition system can be incorporated in all types of vehicle and can be tuned to exhibit much better performance than present traditional ones in engine power curve and efficiency. The advantage of this system would be that it is cheaper to construct and hence serves the purpose of controlling the rate of combustion of engine. Also it gives the user the flexibility to operate as per their requirements.