The key differences between a hot film and hot wire air mass sensor aside from their physical properties, is that the hot film sensor measures a smaller port.
21+ Hot Film Air Mass Meter Images. How does a hot wire air flow meter work? How does hot film mass 6 ( hfm6 ) work?
Hot Film Air Mass Meter from www.bosch-mobility-solutions.com
The airflow sensor or hfm (hot film meter) is hugely important in the performance and fuel economy of the engine. Intake air temperature or ambient pressure changes have no effect on air mass measurement. The sensor takes into account positive and negative intake pulses caused by intake and exhaust valves opening and closing.
To do this, hot film mass air flow sensors measure a small portion of the air entering the engine.
To do this, hot film mass air flow sensors measure a small portion of the air entering the engine. A centrally situated heating resistor on the measuring cell heats a sensor diaphragm and maintains it at a constant temperature. Located just downstream from the airbox. The temperature drops sharply on each side of this controlled heating zone.
