Patent Document ID: 4438497
Application ID: 06285221
Patent Flag: 1

Claim One:
1. A method for controlling the performance of a spark ignited automobile internal combustion engine using exhaust gas recirculation, the engine being responsive to the magnitude of engine control parameters, said method including the steps of: establishing a duration of time to determine the frequency of updating the engine control parameters; determining the energy density output of the engine over the first duration of time, wherein energy density output is the energy output divided by the distance traveled during the first duration of time; maintaining a history of distance traveled and energy output during a plurality of successive consecutive durations of time; estimating the magnitude of energy density output of the engine during the next duration of time; establishing a lookup table for EGR and spark advance as functions of engine torque, engine speed, and engine energy density; selecting a value from the table as a function of the estimated energy density for use during the next duration of time; and controlling the engine EGR and engine spark advance in accordance with the value selected from the table as a function of the estimated energy density thereby improving engine operation for higher efficiency.