To smoothly operate an internal combustion engine during starting and cold idling periods, by calculating the rotational speed of a crankshaft from a speed error between a measured value and a target value, and adjusting a specific supply amount of fuel burnt in each cylinder so as to reduce this speed error.
When an internal combustion engine is operated, a coolant temperature is detected, and also time from a point of rotation starting time when an engine is cranked is measured (S38). Next, a calibration minimum run up speed is found out by using a fuzzy theoretical matrix and so on, on the basis of these values (S42). Also, a minimum idling value is calculated as an idling speed setting point minus calibration dead band (S44), and compared with the run up speed (S46). Then, in case that the run up speed is smaller than the minimum idling speed, the run up speed is determined as an expected engine speed (S48), and in the case of the contrary, the minimum idling speed is determined as the expected engine speed (S50), and a fuel supply amount is controlled according to a speed error between this expected engine speed and a measured speed.
HUSAK PHILIP WILLIAM
WHITTIER STEVEN RAY
BRANDT ERICH PAUL
MAIER WILLIAM J
CULLEN MICHAEL JOHN
