Patent ID: 6834638
Filing Date: 2004-12-28
Classification: F02D,F02P,Y02T

Abstract:
A method for controlling an idle speed of an engine, comprising:detecting an engine speed; detecting an engine load; calculating a target torque ratio on the basis of the engine speed and the engine load using a predetermined relationship between ignition timing and torque ratio, wherein the calculating a torque ratio comprises: calculating a base torque ratio based on the engine speed and the engine load, wherein the calculating a base torque ratio comprises: calculating a first torque ratio based on the engine speed and engine load; calculating a first ignition timing corresponding to the first torque ratio using the predetermined relationship; adjusting the first ignition timing based on intake air temperature and coolant temperature; and calculating the base torque ratio as corresponding to a base ignition timing using the predetermined relationship; and calculating the target torque ratio from the base torque ratio; calculating a target ignition timing corresponding to the target torque ratio using the predetermined relationship; and activating an ignition system of the engine based on the target ignition timing.