| 摘要 |
<p><P>PROBLEM TO BE SOLVED: To diagnose whether engine control is made according to the command irrespective of manipulated variables in the catalyst control for early warming up an engine. <P>SOLUTION: If an actual ignition time lag disagrees with the command value making ignition time lag due to abnormal conditions (if no ignition time angle lag occurs at all against a lag command or if the lag speed is slow compared with such as commanded), ignition timing is faster and engine torque can be less reduced, as that engine revolutions become much higher than the target revolution during usual engine idling time. For this reason, the value when engine is abnormal is larger than that when it is normal due to its more increased revolutions, as shown in the ratio of engine revolutions NE to suction air volume Qa (NE/Qa). Accordingly the use of the ratio of engine revolutions to suction air volume (NE/Qa) as a diagnostic value makes it possible to diagnose the abnormality of an engine without being affected by the size of ignition time lag angle. <P>COPYRIGHT: (C)2007,JPO&INPIT</p> |
