This paper presents the comparative experimental results of an automotive air conditioning (AAC) system charged with refrigerants R1234yf and R134a which were analyzed to find the effect of increasing ambient temperature using energy and exergy-based approaches. The urgencies for such investigation are due to the demand of finding refrigerant both satisfy the performance and also compatible with Kyoto Protocol and EU f-gas regulation. For this aim, a bench-top experimental AAC system was constructed and tested at four different compressor speeds, namely 1000, 1500, 2000, and 2500 rpm. For each compressor speed, the temperatures of the air streams at the inlets of the inside duct was 30 degrees C and varies the outside duct, i.e. T-cond,T- ai, of 30, 35, and 40 degrees C. It was revealed that the AAC system with R1234yf yield comparative performances shown by the higher mass flow rate, comparably less cooling capacity and COP than that of with R134a. The mass flow rates and power absorbed in the compressor get higher as Tcond, ai increase. The biggest contributor to the total exergy destruction of the system is always the compressor and the heat exchangers, i.e. evaporator and condenser, respectively. Thus, in order to improve the system performance, those components should be enhanced.