USB Autoscope

Analytics and diagnosctic equipment for automotive industry

Air flow sensor

Used to determine the amount of air drawn into the engine cylinders. The output signal can be a linearly changing voltage or a changing frequency, depending on type and manufacturer.
Types:

  • Volume air flow sensor;
  • Hot element mass air flow sensor;
  • Hot wire mass air flow sensor;
  • Hot film mass air flow sensor;
  • Kharman vortex air flow sensor.

air_flow_sensor_1

air_flow_sensor_2

Output voltage waveform from a properly functioning volume air flow sensor based on the  potentiometer (BMW 318 1.8i 1996). The waveform was recorded during snap throttle.

air_flow_sensor_3

air_flow_sensor_4

Output voltage waveform from a properly functioning mass air flow sensor. (Toyota Avensis 1.8i 2007).

air_flow_sensor_5

Output voltage waveform from a properly functioning air flow sensor BOSCH HFM5 (Alfa 156 2.0i 2001). Snap throttle.

air_flow_sensor_6

Moment of snap throttle.

air_flow_sensor_7

Output voltage waveform from a properly functioning air flow sensor BOSCH HFM5. Moment of turning the ignition on.

air_flow_sensor_8

Output voltage waveform from a properly functioning mass air flow sensor with a frequency output (Opel Vectra C 2.2i 2006).
KOEO (Key On Engine Off).

air_flow_sensor_9

The engine is at idle.

The USB Oscilloscope program is required for waveform playback. Get the latest USB Oscilloscope program here.