| 摘要 |
The invention has an object to provide a device for determining activation of an exhaust gas sensor which accurately determines a time at which an exhaust gas sensor output is usable, and can suppress an adverse effect caused by use of the exhaust gas sensor output including a large effect of adsorbed species. A time is measured from a time point when a temperature of an air-fuel ratio sensor 48 reaches a predetermined temperature T1, while the air-fuel ratio sensor 48 is warmed up. When the time becomes a predetermined target holding time Te or more, the air-fuel ratio sensor 48 is determined as being in an activation state. The target holding time Te is preferably set at such a length that all adsorbed species adsorbed onto the air-fuel ratio sensor 48 are desorbed, and areas around a sensor element section 50 are completely replaced with an exhaust gas. |
