Patent ID: 7600507

Claim:
An exhaust sensor control system for an exhaust sensor mounted in an exhaust path of an internal combustion engine, wherein said exhaust sensor includes a sensor element for generating an output in accordance with the status of an exhaust gas and a heater for heating said sensor element, the exhaust sensor control system comprising: recovery value counting means for counting the elapsed time or the cumulative intake air amount after internal combustion engine startup as a characteristics recovery value; heater control means for controlling said heater with a recovery target temperature, which is higher than a normal target temperature, set as a target temperature for said sensor element until said characteristics recovery value reaches a recovery determination value; cumulative lean time counting means for counting, after internal combustion engine startup, the cumulative length of time during which the air-fuel ratio is lean; and determination value correction means for increasing said characteristics recovery value or decreasing said recovery determination value with an increase in said cumulative length of time.