| 摘要 |
<p>PURPOSE:To check the generation of smoke and white smoke, by controlling an EGR quantity according to the variation in the case where a corrected engine speed at the time of controlling an engine speed into the specified value is varied at the time when the engine speed is less than the setting value, in case of a device which performs exhaust gas recirculation even at the time of low speed. CONSTITUTION:During engine driving, a normal EGR control duty ratio is calculated from an engine speed and a fuel injection quantity, etc., at an electronic control unit 56. And, whether the engine is in an idle running state or not is judged, and when NO is the case, this control duty ratio is outputted as this time command value. On the other hand, when YES is the case, an idling time exclusive EGR control duty ratio is calculated. And, after a correction duty ratio of this time EGR is retrieved with a map from a difference between this time engine speed correction quantity and the learning value, the correction duty ratio is subtracted from the control duty ratio at the time of idling whereby the control duty ratio coming to this time command value is operated, thus opening of an EGR valve 54 is controlled via a vacuum regulating valve 55.</p> |
