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MAF Sensor

The scan tool displays 0.0-512 g/s. Mass Air Flow (MAF) is the MAF Input Frequency converted to grams of air per second. This indicates the amount of air entering the engine.

The scan tool displays 0-32,000 Hz. The MAF sensor input signal to the PCM is a frequency which varies from around 3,000 Hz at idle to above 7,000 Hz at Wide-Open Throttle (WOT). The PCM converts this frequency signal to grams per second to be displayed on the scan tool as MAF.