[Fl00r]

Из ХЕЛПА.

var DISTANCE:Number = 10;
var keyListener_obj:Object = new Object();
keyListener_obj.onKeyDown = function() {
    switch (Key.getCode()) {
    case Key.LEFT :
    car_mc._x -= DISTANCE;
    break;
    case Key.UP :
    car_mc._y -= DISTANCE;
    break;
    case Key.RIGHT :
    car_mc._x += DISTANCE;
    break;
    case Key.DOWN :
    car_mc._y += DISTANCE;
    break;
    }
};
Key.addListener(keyListener_obj);

где car_mc - имя твоего мува