A TOYOTA escape manual car, when the speed of about 40km/h, the gear is hung into the air or the clutch, the engine appears to swim, the engine speed fluctuates greatly. With the increase of kilometers of vehicles, carbon deposition in the electronic throttle will also increase, resulting in a reduction in throttle air flow. For this reason, engine ECU will increase the intake air volume by increasing throttle opening. However, due to the excessive correction of air in the course of driving and the increase of air intake, the engine speed will rise. After the engine reaches the speed condition of cutting off the fuel, the fuel supply stops, the engine speed decreases, and the engine will have repeated rotational speed fluctuations, that is, the phenomenon of engine travel. After upgrading the engine ECU program and adjusting the correction value of the intake volume, the failure phenomenon disappeared.