To eliminate a noise step and torque fluctuation in a region switching timing between a pilot region and a non-pilot region in a fuel injector for an internal combustion engine for force-feeding fuel from a distributor type fuel injection pump having an electronic control type timer to a fuel injection nozzle.

In the region switching timing from a pilot region to a non-pilot region, after a timer position error (Δθ) between an actual timer position (θr) and a target timer position (θt) becomes a designated value (e.g. 1 to 2° CA) or less and a timer response delay after switching is eliminated, the injection state of the pilot region is switched to the injection state of the non-pilot region. That is, the injection state switching timing from the injection state before switching to the injection state after switching is delayed from the region switching timing from the pilot region to the non-pilot region by a designated delay time (e.g. one to two seconds) corresponding to the timer operation delay, whereby a noise step and torque fluctuation of excessive timing advance or excessive timing lag due to a timer operation delay can be eliminated.