Abstract: A method and apparatus are disclosed for controlling operation of a spark-ignited internal combustion engine by adjusting pulse width of fuel injected into the engine. An initial fuel pulse width is set for respective pairs of engine operating parameters such as engine speed and manifold pressure. The pulse width is adjusted by a control, for each pair of parameters, to obtain maximum performance, for example, as indicated by a torque detector. Each time a pulse width is adjusted, all previously adjusted pulse widths are compared with corresponding pulse widths in stored template fuel maps. The best matched template fuel map is then used in conjunction with all previously adjusted points to create a new operational fuel map to run the engine until a more updated operational fuel map can be created upon additional fuel pulse widths being tuned.