Dual speed fuel delivery system

摘要

A dual speed fuel delivery system for an internal combustion engine in an automotive vehicle includes a fuel pump, a dropping resistor connected to the fuel pump for reducing the voltage required to drive the fuel pump, and a controller for determining an optimum transition point between one of a relatively high and low speed fuel pump operation so that a controlled amount of fuel is delivered to the engine. The controller calculates fuel pressure increase across the fuel pump, determines the minimum fuel pump voltage necessary to drive the fuel pump such that a predetermined amount of fuel is supplied to the engine and determines the current draw of the fuel pump. The controller then calculates the voltage drop across the dropping resistor and compares the resulting voltage with the minimum fuel pump voltage. The controller then selectively by-passes the dropping resistor based on this comparison.