DTC P0101: MAF Sensor Performance: Description

WARNING: This page is about a different car, the 2001 GMC Savana, 2001 Chevrolet RV Cutaway, 2001 Chevrolet Cutaway, and 2001 Chevrolet Chevy Express. However, it is still accessible from the selected car via links, so may be relevant.

Mass Airflow (MAF) sensor is an airflow meter that measures the amount of air entering engine. Powertrain Control Module (PCM) uses MAF sensor frequency signal to provide correct fuel delivery for a wide range of engine speeds and loads. A small quantity of air entering engine indicates deceleration or idle. A large quantity of air entering engine indicates an acceleration or high load situation. MAF sensor has an ignition 1 voltage circuit, a ground circuit and a signal circuit. PCM applies a voltage to sensor on signal circuit. Sensor uses voltage to produce a frequency based on inlet airflow through sensor bore. PCM uses Barometric (BARO) pressure at key on, and engine RPM to calculate a predicted MAF value. PCM compares actual MAF sensor frequency signal to predicted MAF value to determine if signal is stuck based on a lack of variation, or is too low or too high for a given operating condition. DTC P0101 will set if actual MAF sensor frequency signal is not within a predetermined range of calculated MAF value.