Abstract: A system for controlling an ignition timing of an internal combustion engine, in which an ignition timing advancing correction amount is determined based on at least the detected engine coolant temperature, and it is determined whether the engine is under a predetermined cold starting condition. When the result is affirmative, the ignition timing is advanced beyond the MBT. This arrangement is based on the inventors finding that the gas temperature rises at the combustion stroke, but drops little after the expansion stroke. With this, the increased fuel amount for compensating the engine output loss caused by ignition timing advancement can effectively be utilized to heat the engine coolant, thereby facilitating and improving the engine warm-up.

Abstract: An engine comprising a spark plug and a fuel injector in a combustion chamber and a temperature sensor used to judge if the gas temperature in the combustion chamber is a temperature at which self-ignition occurs when a spark is generated. Based on this judgement, a valve timing device is used to control the opening timing of the intake valve and maintain the gas temperature at a temperature at which self-ignition occurs when a spark is generated.

Abstract: A device for suppressing knocks in internal combustion engines, in which the ignition firing point is adjusted after knocking has occurred, and this knock control is only activated in response to specifiable thermal conditions in the internal combustion engine. The gas-inlet temperature in the combustion chamber of the internal combustion engine is ascertained for the valuation of the thermal conditions of the internal combustion engine and for switching the knock control into the active state.

Abstract: A two-cycle internal combustion engine has an ignition timing that varies with engine speed. A plurality of ignition patterns (the relationship between ignition timing and engine speed) are used. The engine exhaust gas temperature is sensed and is used to determine the particular ignition pattern used at a particular time.

Abstract: An electronic control unit for an internal combustion engine is able to accurately identify cylinders even in such a case as starting an engine while the engine is still cold or with a deteriorated battery or even if the engine is started hurriedly, or hastened start is repeated. In the electronic control unit that measures the cycle of a signal issued from a crank angle sensor and identifies a cylinder according to a calculated value based on the cycle to control the internal combustion engine, the ratio of a present signal cycle and a previous signal cycle is compared with a judgment value, and cylinder identification is effected based on a time series pattern of the ratio, and the judgment value is changed on the basis of at least one of the temperature of the engine and battery voltage.