Abstract: In an unthrottled fuel injection type internal combustion engine, a controlled injection logic to generate a first pulse train whose frequency varies with the accelerator position, N cylinder chambers (CCH's) 11, FIG. 1 ), each with a piston, and a distributor (111, FIG. 4) comprising N first devices and a rotor 109 for generating a second pulse each rotation past a first device, N fuel injection/ignition devices (FIGS. 1-2) each having a fuel ignition element (FIE) extending into a CCH to ignite the injected fuel and a fuel injector for injecting fuel towards each FIE at certain time intervals after the rotor passes the associated first device, a first counter for measuring, in time/degree of engine crankshaft rotation (ECR), the time required for M.degree. of ECR, and for determining the rotor angular velocity.