Ford Focus 2000-05

Vane Air Flow (VAF) Meter



The Vane Air Flow (VAF) meter, also known as a Volume Air Flow Meter, measures the air flowing into the engine. The meter contains a movable vane which is connected to a potentiometer. As air flows through the meter, the movable vane and potentiometer change position and provide an input to the PCM. The PCM can then translate the vane position into the volume of air flowing into the engine.

The VAF meter is mounted in the following locations:

1.8L engines: between the air cleaner and throttle body


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Fig. VAF meter wiring schematic and connector terminal identification-1.8L engines

  1. Make sure the ignition key is OFF.
  3. Connect jumper wires from the sensor connector to the wiring harness. This permits the engine to operate normally while you check the sensor.
  5. Connect a Digital Volt Ohmmeter (DVOM), set to read voltage, between sensor terminals VAF and SIG RTN.
  7. Turn the key ON and access the VAF meter measuring vane.
  9. With the vane fully closed, the voltage reading should be 4.5-5 volts.
  11. Slowly move the vane to the fully open position. As the vane moves through its travel, the voltage should drop slowly and smoothly. When the vane reaches the end of its travel, the voltage reading should be 0.5-1.5 volts.
  13. If the voltage readings are not within specifications, replace the VAF meter.