To provide a combustion control device for a diesel engine, which avoids a reduction in a premixed combustion mode area and prevents the instability of engine operation caused by frequent switching of a combustion mode, even if a driver performs wavy accelerator operation in an upper limit load area within the premixed combustion mode area.
When the driver performs the wavy accelerator operation in the upper limit load area set to a high-load side in the operation area of a premixed combustion mode, a wavy operation flag F is set, and offset rail pressure higher than usual is applied as a target value in the upper limit load area until the wavy operation flag F is reset by the completion of the wavy accelerator operation. Thereby, it is possible to prevent performance of a normal combustion mode in the upper limit load area where the premixed combustion mode is originally performed.
TANABE YOSHIKI
NAKAYAMA SHINJI
