| 摘要 |
PROBLEM TO BE SOLVED: To accurately control an air-fuel ratio to a target air-fuel ratio. SOLUTION: An operation controller is provided with a switching means performing a switch between first combustion, in which soot is hardly generated because a recirculation emission gas amount fed into a combustion chamber 5 is higher than a recirculation emission gas amount generating peak amount of soot, and second combustion, in which the recirculation emission gas amount fed to the combustion chamber is lower than that generating a peak amount of soot, an air-fuel ratio sensor 27a arranged in an engine exhaust passage for detecting an air-fuel ratio, and a controlling means performing feedback control of the air-fuel ratio on the basis of an output value of the air-fuel ratio sensor so that the air-fuel ratio becomes a target ratio. When a rich air-fuel ratio is attained during the first combustion, output value correcting processing is carried out for correcting the output value of the air-fuel ratio sensor. |
