Inter-cylinder air-fuel ratio variation abnormality detection apparatus for multicylinder internal combustion engine

摘要: An inter-cylinder air-fuel ratio variation abnormality detection apparatus is disclosed. The determines imbalance of an among the cylinders based on a difference between index values correlated with crank angular velocities detected in set opposite belonging to different banks and having angles from one another by 360°; carries out feedback process for controlling amount injected fuel each banks, wherein comprises correction unit correcting, before determining imbalance, direction combustion improvement that are bank identical cylinder most deviating value standard all being other than value.