Engine stop/start and cylinder deactivation is gaining acceptance as a trend by car manufacturers to improve fuel consumption of passenger cars. The engine stop/start technology switches off the engine to eliminate the usage of fuel whenever the vehicle is at a stand-still, typically in a highly congested area of an urban driving. The inherent issue with the implementation of stop/start technology in Southeast Asia tropical climate such as Malaysia is the requirement for the air-conditioning system to be in constant operation, which reduces the duration of engine switch-off during vehicle stops and consequently nullifying the benefit of the system. On the other hand, cylinder deactivation technology improves the fuel consumption at certain conditions during low to medium vehicle speed when the engine is at part load operation only. This study evaluates the fuel consumption between stop/start and cylinder deactivation technologies over the actual Malaysian urban driving conditions as one of Southeast Asia countries. A 1.6L PFI 4-cylinder engine is modelled in a one-dimensional gas dynamics software to predict the fuel consumption. A transient driving profile based on torque obtained from actual road test over an urban driving route is simulated and fuel consumption is analysed and compared with New European Drive Cycle. The results provide useful insight and enable manufacturers to assess and consider which technology offers more genuine impact on the fuel consumption and the challenges under urban driving of a Southeast Asia tropical climate area such as Malaysia.