Fuel pressure control apparatus for cylinder injection type internal combustion engine

摘要

A fuel pressure control apparatus for a cylinder injection type engine capable of restarting the engine without fail notwithstanding increase of fuel pressure due to temperature rise immediately after stoppage of engine operation. Fuel is supplied from a high pressure fuel pump ( 5 ) to a fuel rail ( 2 ) to be injected by fuel injection valves ( 1 ) into combustion chambers ( 20 ) of cylinders. An ECU ( 10 ) estimates increment (DeltaP) of the fuel pressure (PF) within the fuel rail ( 2 ) after stoppage of the engine operation on the basis of a water temperature (THW) and an intake air temperature (THA) to restrict a maximum value of a desired fuel pressure (Po) so that a sum value (PM) of the desired fuel pressure (Po) and the increment (DeltaP) does not exceed the critical actuation pressure (Pi) of the fuel injection valve ( 1 ).