Mass Air Flow Sensor
Mass Air Flow (MAF) Sensor:
The Mass Air Flow (MAF) sensor measures the amount of air which passes through the sensor. The PCM uses this information to determine the operating condition of the engine in order to control the fuel delivery. A large quantity of air indicates acceleration. A small quantity of air indicates deceleration or idle.
The scan tool reads the MAF value and displays it in grams per second (g/s). The MAF sensor displays between 4 g/s-9 g/s at idle on a fully warmed up engine. The MAF sensor values should change rather quickly on acceleration, but the MAF sensor values should remain fairly stable at any given RPM. The following DTCs set when the PCM detects a malfunction in the MAF sensor circuit:
^ DTC P0101 Mass Air Flow System Performance
^ DTC P0102 MAF Sensor Circuit Low Frequency
^ DTC P0103 MAF Sensor Circuit High Frequency