FUEL-INJECTION CONTROLLER FOR ENGINE

摘要

A fuel-injection controller for an engine (1) provided with an intake-passage fuel-injection valve (10) via which fuel is injected into an intake port (4), and an in-cylinder fuel-injection valve (11) via which fuel pressurized by a high-pressure pump (20) is injected into a combustion chamber (3), wherein the high-pressure pump (20) has a plunger for pressurizing fuel in a pressurization chamber and a spill valve for opening or closing a route via which fuel is supplied to the pressurization chamber, the plunger performing four cycles of reciprocating movement within the pressurization chamber for each rotation made by a driveshaft driven by the engine (1). A control unit (32) for controlling the driving of the spill valve is provided. When fuel is to be injected via the in-cylinder-fuel-injection valve (11) and medium-load operation is in effect; i.e., when the operating load is lower than what is encountered in high-load operation, the control unit (32) causes the spill valve to be driven two times for each rotation made by the driveshaft instead of four times, which is the number of times the spill valve is driven under high-load operation.