Patent ID: 7255089

Claim:
A control device for an engine having an ignition device, comprising: a sensor which detects a knocking in a combustion chamber of the engine; and a controller which: estimates a knocking-correlated parameter, which is a parameter having a correlation with the knocking, on a basis of a knocking detection result; predicts a knocking occurrence timing of the combustion chamber on a basis of the estimated knocking-correlated parameter; calculates a knocking limit ignition timing, which is an ignition timing furthest toward an advanced side at which the knocking does not occur on a basis of the predicted knocking occurrence timing; and controls the ignition device to perform a spark ignition at the calculated knocking limit ignition timing; estimates a pressure increase amount in the combustion chamber produced by the knocking on the basis of the predicted knocking occurrence timing and an engine operating condition; calculates a basic ignition timing corresponding to the engine operating condition; and sets a value obtained by correcting the basic ignition timing to a retarded side as the knocking limit ignition timing on a basis of the pressure increase amount in the combustion chamber.