The invention is directed to a fuel injection pump having an adjusting piston subject to a fluid-pressurized restoring force varied in accordance with engine operating parameters. In a typical fuel injection pump of this type, such as is known from German Offenlegungsschrift No. 26 48 043.3, the adjusting piston which serves to adjust the instant of injection is subjected to the rpm-dependent pressure which prevails in the suction chamber of the fuel injection pump. The rpm-dependent pressure is generated with the aid of a pressure control valve. In order to adjust the instant of injection toward an "early" setting during starting and engine warmup, the hydraulic pressure is increased by reducing the quantity of fuel flowing out of the suction chamber. To accomplish this result, one embodiment of fuel injection pump is provided with a supplementary outlet passage extending from the suction chamber, which outlet is closed during starting and warmup.