| 摘要 |
<P>PROBLEM TO BE SOLVED: To provide an air-fuel ratio control device capable of suppressing deterioration of emission characteristics when starting the internal combustion engine, considering an effect that an exhaust gas component, which is absorbed on an air-fuel ratio sensor while the internal combustion engine stops, provides to an output of the air-fuel ratio sensor. <P>SOLUTION: In a high temperature start, an air-fuel ratio F/B control using the output of the air-fuel ratio sensor is executed at or after a semi-activated state judging time t2 at which an admittance value As of the air-fuel ratio sensor becomes a standard value A1. In a low temperature start, because a shift of the air-fuel ratio sensor output from an actual air-fuel ratio is not converged at a time t2, the air-fuel ratio output is masked with a stoichiometrically until a regular activated state judging time t3 at which an admittance value As becomes a standard value A2. <P>COPYRIGHT: (C)2008,JPO&INPIT |
