摘要 |
An internal combustion engine includes a turbocharger, a variable valve gear, an A/F sensor in an exhaust passage, A/F feedback control means, and scavenge A/F control means. The variable valve gear drives intake and exhaust valves, and can drive with a valve open characteristic with valve overlap. The A/F feedback control means performs feedback correction of a fuel injection amount based on an A/F sensor output, and acquires a learning value of information relating to A/F control from a feedback correction amount. The scavenge A/F control means carries out A/F control by a value learned during an operation of the engine with non-scavenge valve open characteristic, when the variable valve gear is operated with the scavenge valve open characteristic. The scavenge valve open characteristic has a valve overlap amount of such a degree that blow-by of intake air occurs in an intake stroke during a turbocharger operation. |