Patent ID: 7421329

Claim:
A system for controlling an engine, comprising: a controller; a tachometer configured to provide pulses to the controller; a sensor configured to measure operating parameters and output a corresponding signal to the controller; a memory configured to store data for calculating engine fuel requirements; and a drive circuit, wherein the controller controls an on-time and an off-time of a fuel injector using modulation of currents capable of opening and closing the fuel injector, wherein within the fUel injector on-time, the controller provides a current capable of opening the fUel injector for a first time period within the on-time and a modulated current capable of maintaining the fuel injector in an open state for a second time period, wherein the second time period comprises a remaining portion of the on-time, wherein the drive circuit controls peak current duration to open the fuel injector and reduces holding current to maintain the fuel injector in an open state, and wherein the controller controls the drive circuit according to the data and based on the signal from the sensor.