But during fuel control process the Air-Fuel-Ratio (AFR) shows an excursion,resulting in a low conversion efficiency of TWC because of the inexact control whichmaybe on account of the engine consistency and aging.

• 但是在发动机燃油控制过程中,由于发动机一致性以及由发动机老化带来的燃油控制精确性问题,空燃比偏离化学计量比,使TWC转化率下降,导致排放大量增加。