PURPOSE: To improve operation responsiveness and fuel consumption by setting a throttle opening characteristic so as to obtain respectively a minimum acceleration change rate at the time of providing a request of attaching much importance to running performance and a minimum fuel consumption rate at the time of providing a request of attaching much importance to fuel consumption performance.

CONSTITUTION: Output torque of an engine 1 is transmitted to a drive wheel 4 through an automatic transmission 2 and a propeller shaft 3. On the other hand, a throttle valve 6 is arranged in an intake air passage 5 of the engine 1 and driven to be opened and closed by an actuator 7. The actuator 7 is controlled to be driven by a controller 8 based on each detection signal from an accelerator opening sensor 9, mode switch 10, EGI computer 11 and a car speed sensor 12. Here in the controller 8, a throttle opening characteristic is set so as to obtain a minimum accelerator change rate when provided a request of attaching much importance to running performance. In this way, a car speed change relating to an accelerator opening is generated to correspond to intention of a driver.