Engine Stop/Start System (ESS) promises to reduce greenhouse gas emissions and improve fuel economy of the vehicles. In the previous work of the Authors, emphasis was laid in bridging the gap of improvement in fuel economy promised by ESS under standard laboratory conditions and actual driving conditions. Findings from the practical studies lead to a conclusion that ESS is not so popular among the customers, due to the complexities of the system operation and poor integration of the system design with the driver behavior. In addition, due to various functional safety requirements, and traffic conditions, the actual benefits of ESS are reduced. A slightly modified control algorithm was proposed and proven for the local driving conditions in India, which was developed through Design Thinking Methodology. During the development, challenge was the task of adapting the ESS control algorithm to the typical driver behavior during an idle stop, to maximize the auto engine stop events in actual driving conditions. The ways in which a given driver behaves on the controls of the vehicles like Clutch and Brake Pedals, Gear Shift Lever were not uniform across the demography of study and varied significantly. In addition, Authors also discovered that some drivers also used the controls like parking brake during an idle stop. Thus, a concept of autonomous learning algorithm was envisaged, which would learn the driver behavior on the controls which influences the functions of ESS and then adapt the same conditions to trigger the auto engine stop and restart. This was aimed at improving the user experience and yet ensure the benefits of the ESS. In this paper, the findings from previous works are analyzed to make grounds for the new submission and to identify the need for User Experience of ESS. The solution implemented to detect the driver behavior from the set of possible ways is discussed in detail and simulation case studies are discussed to ascertain the benefits of the new algorithm.