Control unit for internal combustion engine

摘要

The invention relates to a control unit (16) for an internal combustion engine (1) which can activate a three way catalyst (11) at the early stage and can lessen the deterioration of the exhaust in an internal combustion engine such as HC, CO, and NOx, etc. from the exhaust gas when starting. The internal combustion engine (1) is provided with said three way catalyst (11) and an HC adsorbent (18) on an exhaust side. The control unit (16) alternately controls the A/F between a rich state and a lean state in order to quicken the activation of the three way catalyst (11) when the internal combustion engine (1) starts. The control unit has a means for detecting completion of the evaporation of moisture in the three way catalyst, as well as means for detecting the temperature of the catalyst. The ignition time is retarded until moisture evaporates.