What controls the speed of the fuel pump?

摘要

The fuel requirements for an engine were easy back in the days of mechanical fuel pumps. The faster the engine turned and as the level in the fuel bowls dropped, more fuel became available for the circuits in the carburetor. As fuel injection took over, the first electric fuel pump circuits were just a relay and fuse on the power side and the ignition switch on the control side. Control over the fuel pressure was performed with an analog regulator that adjusted for loads with a vacuum signal.