Mass Airflow Sensor

The Mass Airflow (MAF) sensor measures flow of air entering the engine in grams per second. This measurement of airflow is a reflection of engine load (throttle opening and air volume), similar to the relationship of engine load to MAP or vacuum sensor signal. MAF signal should remain relatively constant at cruise, gradually changing with throttle angle and rapidly changing on sudden acceleration. PCM uses MAF information to control fuel delivery. Sensor produces a frequency signal which cannot be easily measured in testing (32-150 Hertz). This varying signal is proportional to airflow. Failure in MAF sensor circuit should set a related diagnostic trouble code.