DTC P0101: Mass Airflow Sensor Performance: Description

Mass Airflow (MAF) sensor is an airflow meter that measures amount of air that enters engine. Powertrain Control Module (PCM) uses MAF sensor signal in order to provide correct fuel delivery for a wide range of engine speeds and loads. A small quantity of air entering the engine indicates deceleration or idle condition. A large quantity of air entering the engine indicates an acceleration or a high load situation. MAF sensor has an ignition 1 voltage circuit, a ground circuit, and a signal circuit. PCM applies a voltage to the sensor on the signal circuit. The sensor uses the voltage in order to produce a frequency that is based on inlet airflow through the sensor bore. PCM uses Barometric Pressure (BARO), Throttle Position (TP), Intake Air Temperature (IAT), and engine RPM in order to calculate a predicted MAF value. PCM compares actual MAF sensor signal to predicted MAF value. This comparison determines the following conditions: signal is stuck based on a lack of variation, or signal is too low or too high for a given operating condition. DTC P0101 will set if actual MAF sensor signal is not within a predetermined range of the calculated value.