An engine control device can include a throttle valve for adjusting an amount of air supplied to an engine, operation amount detecting sensors for detecting an operation amount of a throttle lever, a motor for driving the throttle valve between open and closed positions according to detection values of the operation amount detecting sensor 21a or the like, and throttle opening detecting sensors for detecting an opening of the throttle valve is provided with a limp-home mechanism for keeping the throttle valve in a mechanically neutral position when an abnormality occurs. When the throttle valve is in the mechanically neutral position, an ignition timing control can be switched in a stepwise manner over a predetermined time period from a regular ignition timing control to a limp-home ignition timing control.