Ignition timing control device for direct-injection spark-ignition internal combustion engine

摘要

PROBLEM TO BE SOLVED: To set an ignition timing by a system optimum to a uniform combustion period and a stratified change combustion period and by a necessary minimum limit computation load. SOLUTION: It is decided at S31 whether uniform combustion is demanded or stratification combustion is demanded, and when uniform combustion is demanded, an ignition timing ADVH equivalent to MBT for uniform combustion is computed at S32 and 33 by a preset MBT arithmetic expression based on the parameter of an engine operation state. When stratified charge combustion is demanded, the ignition timing ADVH for stratified change combustion is retrieved at S34 based on the parameter of an engine operation state and by referring to a preset map.