Abstract: An electronic fuel injection system wherein fuel injectors are turned on by electrical pulses whose time periods are controlled in accordance with information received from various engine condition sensors. A primary pulse is transmitted for each revolution of the engine and this pulse is used to turn on the fuel injectors for the controlled time period. Auxiliary pulses for acceleration enrichment are also used to turn on the same fuel injectors for a time period that is controlled by throttle conditions. A pulse time addition circuit is provided so that the time period of an acceleration enrichment pulse is added to the time period of a primary pulse even when the acceleration enrichment pulse occurs during the period of the primary pulse thereby insuring that the desired total amount of fuel is added to the engine regardless of the sequence of occurrence of the control pulses.