We do have a mass-airflow Sensor.
Is right in front of the Throttle body, almost permanently mounted on the black hose coming from the Intercooler. You will see a vacum line and a conector sticking out of it. That is the way the car know how much air is going into the engine. The other sensors on the manifold and throttle body are for air Presure . The computer takes this readings and makes the "Correct" fuel ratio, and later verified by the two Oxygen sensors on the exaust side.
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