Engine air-fuel ratio controller

摘要

A warmup fuel amount corresponding to a predetermined heavy fuel is set to control an air-fuel ratio of an air-fuel mixture supplied to an engine during warmup. A correction amount based on a difference between a post-warmup engine speed variation and a first reference value is stored, and a warmup fuel amount decreased by this correction is supplied to the engine on the next startup occasion. In this way the sensitivity of air-fuel ratio control during startup when fuels of different nature are used, is enhanced.