Abstract: A fuel feeding apparatus for an internal combustion engine, in which a thermal type flow sensor is disposed in a bypass air path supplying bypass air from a point upstream of a Venturi portion formed in a main air-intake path to the Venturi portion, and the quantity of air flowing through the bypass air path is controlled by a solenoid unit so that the output signal of the thermal type flow sensor attains coincidence with a pre-set level. A fuel-metering valve actuated by the solenoid unit meters the quantity of fuel meeting a variation of the quantity of intake air being supplied to the engine so as to inject the metered quantity of fuel in a continuous flow into the main air-intake path. An oxygen sensor senses the concentration of oxygen in engine exhaust gases, and, on the basis of the output signal of the oxygen sensor, the value of the pre-set level is modified so that the rate of excess air in engine exhaust gases can be maintained to be .lambda.=1.

Abstract: An intake air amount detecting system which comprises:a temperature-dependent resistor disposed in an intake air path of an internal combustion engine;a sensor control circuit which feeds a heating current to the temperature-dependent resistor, which detects the change in resistance of the temperature-dependent resistor, which amplifies the detected signal, which effects the compensation depending upon the temperature of the intake air, and which controls the heating current in order to maintain the temperature of the temperature-dependent resistor constant; andan operation circuit which converts a signal that represents the heating current into an intake air flow rate;wherein the sensor control circuit is provided with a response-adjusting circuit which delays the response of the heating current only when the intake air flow rate decreases.