Electronic fuel injection with fuel optimization and exhaust pressure feedback

Claim 1

In a multi-cylinder internal combustion engine having an electronically controlled fuel-injection system wherein a pulse generator provides, to associated fuel injectors, fuel-injection control pulses of time duration proportioned to engine speed and to other factors including desired throttle setting and manifold temperature, and wherein a fuel pump delivers fuel at a predetermined pressure from a tank to a manifold serving the fuel injectors for the respective cylinders, and a pressure regulator associated with said fuel tank and with said fuel pump maintains substantially constant said predetermined pressure and thereby maintains a controlled pressure differential across said fuel injectors, the improvement comprising a pulse generator control unit having no manifold absolute pressure detector coupled thereto, means for monitoring the exhaust back pressure from said internal combustion engine and means responsive to said monitoring means and coupled to said pressure regulator for effecting control of said pressure differential as a function of changes in said exhaust back pressure.