Air Flow Meter/Sensor: Description and Operation

OPERATION
The Mass Air Flow (MAF) sensor measures the amount of air which passes through it. The Powertrain Control Module (PCM) uses this information to determine the operating condition of the engine, to control fuel delivery. A large quantity of air indicates acceleration, while a small quantity indicates deceleration or idle.

The Tech 1 scan tool reads the MAF value and displays it in grams per second. It should read between 4-7 grams per second on a fully warmed up idling engine. Values should change rather quickly on acceleration, but values should remain fairly stable at any given RPM. A failure in the MAF sensor or circuit should set Diagnostic Trouble Code (DTC) P0101.