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

(Some people have issue connecting. LEMON is investigating. For now, use Firefox or change your DNS server)

Or, hide this message: temporarily or permanently

Air Flow Meter/Sensor: Description and Operation








OPERATION
- The volume air flow sensor is incorporated within the air cleaner, it functions to convert the amount of engine air intake to pulse signals of a frequency proportional to the amount of engine air intake, and to input those signals to the engine control module. The engine control module then, based upon those signals, calculates the amount of fuel injection, etc.
- The power for the volume air flow sensor is supplied from the MFI relay to the volume air flow sensor, and is grounded at the engine control module. The volume air flow sensor, by intermitting the flow of the 5 V voltage applied from the engine control module, produces pulse signals.