Abstract:According to the need of vehicle roadway test, a fuel consumption measuring and velocity testing intelligent system was designed and realized. This system used the ethernet port of the computer to create virtual serial ports and chosen RS-485 Means of communication in order to improve the efficiency of serial ports. Besides, for the sake of achieving the real-time monitoring of automobile comprehensive performance tests, this paper programmed on serial ports based on VC++6.0, and designed the software operation interfacefor receiving and displaying the data real-timely, which were measured by the lower computer. The experimental results of the real vehicle showed that fuel consumption measuring and velocity testing intelligent system had the advanced and reliable measurement method as well as the high accuracyon the premise of considering the cost.