| 摘要 |
PROBLEM TO BE SOLVED: To materialize quick activation of an air fuel ratio sensor at a time of start and to reduce exhaust emission quantity by reducing engine load by alternator drive right after start. SOLUTION: O2 sensors 10, 11 are provided on an upstream side and a downstream side of a catalyst 8. When starting the engine (Time t1), heater energization amount FDUTY of a heater 10a built in the front O2 sensor 10 is set to 100% and heater energization amount RDUTY of a heater 11a built in the rear O2 sensor 11 is set to a value subtracting rear O2 heater energization subtraction value DECDUTY from rear O2 heater energization HTRDUTY. Heater energization amount FDUTY of the front O2 sensor 10 is dropped when the front O2 sensor 10 is activated (time t2), and rear O2 heater energization subtraction value DECDUTY is reduced to raise heater energization amount RDUYT. COPYRIGHT: (C)2006,JPO&NCIPI
|
