The pollutant gases produced by vehicle emission is carbon monoxide (CO), hydro carbon (HC), carbon dioxide (CO2), and nitrogen oxides (NOx). The vehicles in Indonesia increased in number from year to year. Increasing the number of these vehicles will be directly increasing the higher concentration of gases CO, HC, CO2, NOx in the air. The concentration of gases increases the effect of global warming.The objective of this project aims to be created and developed a tool to test the levels of exhaust emissions
produced by vehicles. The method used in this research is the method of literature study, interview, observation, interview and design. This tool can detect levels of vehicle exhaust gas by using a gas sensor MQ-7 and MQ-2 for measuring CO and HC. The system process using a microcontroller Arduino nano that will display on LCD the value the merits of the vehicle exhaust. It uses a buzzer as an indicator of the threshold value of gases, and the result is proven by the display in the LCD. The whole system testing shows that the system runs well. It is proven when it was tested with the gasoline vehicle, the tool shows the value of CO of the vehicle. Overall concluded that exhaust emissions test equipment that has been created is working properly. It is proven when it was tested in the laboratory, the tool shows the value of CO and HC on the LCD.