Patent ID: 7693647

Claim:
An intake air amount calculating system for calculating an intake air amount of an internal combustion engine, comprising: an air flow meter disposed in an intake passage of the engine that measures the intake air amount, the air flow meter comprising a microchip device, a heater portion and a temperature sensing portion; an intake air temperature sensor disposed in the intake passage that measures an intake air temperature; a start predicting unit that predicts start of the engine; an intake air temperature sensor activating unit that activates the intake air temperature sensor when the start predicting unit predicts start of the engine; a pre-heating unit that causes the heater portion to be heated in advance when the start predicting unit predicts start of the engine; an intake air temperature acquiring unit that acquires the intake air temperature sensed by the temperature sensing portion, prior to pre-heating of the heater portion; and a calibrating unit that calibrates characteristics of the temperature sensing portion if a difference between the intake air temperature acquired by the intake air temperature acquiring unit and the intake air temperature sensed by the intake air temperature sensor is equal to or below a predetermined value, after completion of start-up of the intake air temperature sensor.