Operation CHARM: Car repair manuals for everyone.
Manuals through 2025 now available!

Our trusted friends have launched a new website named LEMON, which has newer manuals. It also contains all the CHARM manuals.

LEMON is the spiritual successor to CHARM, I recommend you try it!

Link: lemon-manuals.la or lemon-manuals.org.ua

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Air Flow Meter/Sensor: Description and Operation

Mass Air Flow Sensor:






The Mass Air Flow (MAF) sensor measures the flow of air which passes through it in a given time. It does this by measuring the electrical power required to maintain the sensing element at a specific number of degrees Celsius above the incoming air temperature. As the air enters the sample tube it passes over and cools the sensing element, which then requires additional current to maintain the prescribed uniform temperature. The PCM uses this information to monitor the operating condition of the engine for fuel delivery calculations.