| 摘要 |
PURPOSE:To improve a rate of fuel consumption as well as to secure smooth roadability, by making a controller perform lean control during constant-speed running control, while making a theoretical air-fuel ratio controllable if a throttle valve comes open even in time of said constant-speed running control. CONSTITUTION:If an idle switch is turned on, whether idleness or constant-speed running control is discriminated. During constant-speed running control, it shifts to lean control. When a driver steps on an accelerator pedal, it is rid of the lean control even in time of the constant-speed running control. In the case where an engine state is unstable, it shifts to theoretical air-fuel ratio control, improving a degree of responsiveness. Thus, a rate of fuel consumption in a constant-speed period is improvable and, what is more, smooth roadability is securable. |
