microprocessor become inseparable in yet another alternative the pump comes with its own microchip and when the pump is installed on the engine the microchip is plugged into the control system where it becomes an extension of the microprocessor memory when the pump is replaced the microchip is replaced too the above described system is applicable to all types of electromagnetic pumps 1 the nondistributor multiplunger type in which each plunger is controlled by a separate solenoid and supplies fuel to one of the engine cylinders 2 the semi distributor multiplunger type in which each plunger supplies fuel to one of the cylinders but one solenoid controls operation of several plungers and 3 the distributor type pump in which a single plunger controlled by a single solenoid successively delivers fuel to all cylinders of the engine in the latter two cases the control system will be programmed to generate a succession of signals all sent to the same solenoid each signal will be individually tailored to control fuel delivery to one of the engine cylinders in addition to improvement in the cylinder to cylinder fuel distribution the self adjusting system can also improve the cycle to cycle fuel distribution in cases when the cycle to cycle maldistribution follows a discernible cyclical pattern the pump memory can contain information on this pattern at specific test points so that the control system can make suitable corrections in the solenoid pulse width following specific sequence corresponding to the known pattern of cyclical variations in fuel delivery to make sure that the sequence of corrections is in proper synchronization with the sequence of variations the control system receives a synchronizing signal from a sensor capable of recognizing a selected reference cycle such as peak fuel.