Automobile fuel control system

Claim 1

A fuel control system for an automobile engine which comprises an air-fuel ratio detector for detecting the air-fuel ratio of a combustible mixture to be supplied to the engine; an engine rotational speed detector for detecting the engine rotational speed; an engine load detector for detecting the engine load imposed on the engine; a first storage means storing, at address locations determined by respective combinations of engine rotational speed and engine load, a standard control value for the control of the amount of fuel to be supplied during a particular engine operating condition; a second storage means storing, for each of a plurality of zones defined by the engine rotational speed and the engine load, a correction control value for the correction of the standard control value; a control signal output means for, when the engine is operating under a high load condition with the engine load being higher than a predetermined value, outputting, as the control value of a control signal, a control value given by the first and second storage means to an engine operating condition then assumed by the engine and, when the engine is operating under a condition with the engine load being consequently lower than the predetermined value, for correcting the control value given by the first and second storage means to the engine operating condition then assumed by the engine, in such a manner, that the air-fuel ratio of the combustible mixture is rendered to settle within a predetermined value on the basis of an output from the air-fuel ratio detector, and outputting the finally corrected control value as the control value of the control signal; a correction control value modifying means for, during the engine operating condition other than the high load operation condition, modifying on the basis of the control value of the control signal from the control signal output means the correction control value stored in the second storage means and aasociated with a first zone in which the engine is then operating, so that the air-fuel ratio of the combustible mixture to be controlled by the control value given by the first and second storage means can attain the predetermined value, and for modifying, on the basis of the correction control value for said first zone, the correction control value that is stored in the second storage means at a second zone corresponding to the high load engine operating condition at the same engine rotational speed as in said first zone; and a fuel supplying means adapted to receive the control signal from the control signal output means for controlling the flow of fuel to be supplied to the engine.