Abstract: In a magnetic valve controlled fuel injector for a multi-cylinder internal combustion engine with a nozzle needle movably disposed in the injector housing and spring-biased onto a nozzle needle seat wherein high pressure fuel supplied to the nozzle needle through a fuel admission passage lifts the nozzle needle off its seat for discharging fuel therefrom, a control piston with a valve portion is disposed in the injector housing and controlled by an electromagnetic valve for admitting fuel under pressure to the fuel admission passage and a pressure piston is movably disposed in a pressure space formed at one end of a space receiving the nozzle needle spring which, with one end biases the nozzle needle toward its closed position and is supported at its other end by the pressure piston and a throttled communication passage extends between the fuel admission passage and the pressure space for moving the pressure piston toward the nozzle needle when the pressure in the fuel admission passage remains because of a d