Air Flow Meter/Sensor: Description and Operation

Vane Air Flow (VAF) Meter:

The Vane Air Flow (VAF) meter measures air flowing into the engine and is mounted between the air cleaner and the throttle body assembly. The VAF meter contains a potentiometer that connects to a movable vane. As air flows through the VAF meter, the movable vane and potentiometer change position and provide an input to the Electronic Control Assembly (ECA) with vane position information. Inside the VAF meter is a fuel pump switch that provides a ground for the fuel pump circuit after the engine has started. The ECA can translate vane position information into the volume of air flowing into the engine to make adjustments to the air/fuel mixture, injector timing, and ignition timing.