Express 1/2 Ton Van V8-305 5.0L VIN M SFI (1998)
Mass Air Flow (MAF) Sensor: Description and Operation
Mass Air Flow (MAF) Sensor
The Mass Air Flow (MAF) sensor measures the amount of air which passes through it. The VCM uses this information to determine the operating
condition of the engine, to control 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 (gm/Sec). At idle, it should read between 5-7 gm/Sec on a fully warmed up
engine.
Values should change rather quickly on acceleration, but values should remain fairly stable at any given RPM. When the VCM detects a
malfunction in the MAF sensor circuit, the following Diagnostic Trouble Code (DTC)s will set:
^
DTC P0101 system performance.
^
DTC P0102 frequency low.
^
DTC P0103 frequency high.
