Gus,
     The amount of air flowing through an engine is depended on both RPM=20
and load. If the RPM is kept constant but the load is increased then the=20
throttle has to be opened up to maintain the RPM at the increased load.=20
The cylinders are now being more thoroughly filled and the amount of air=20
flowing through the engine increases even though the RPM is constant and=20
vice-a-versa.
     Now lets take a constant load but increasing RPM. For our=20
discussion the load  of an engine that is not connected to anything=20
stays constant even though the RPM changes. This is not entirely true as=20
internal losses increase as the RPM goes up but for this discussion we=20
will state that the load is constant. So as RPM increases the amount of=20
air flowing through the engine increases because the cylinders are=20
moving more air per second. And vice-a-versa.
     So the vane in the airflow meter will move in accordance with this=20
increasing and decreasing airflow. The thermistor in the airflow meter=20
is the air temperature sensor. In conjunction with the water temperature=20
sensor the computer then determines which fuel map to use.
Thanks,
rich!

On 11/5/2015 2:14 PM, 99guspuppet wrote:
> I mentioned that I opened up my AFM.
> I expected the wiper on the AFM potentiometer to
> track the engine RPM as I assumed RPM and airflow were
> linked proportionally.
> Instead I saw the wiper move up with increasing RPM,
> then drop back.  Since the RPM was hard to control
> ( the reason why I am looking at engine parts ) I was unable
> to make a reliable observation of exactly what happened.
> Any comments ?
>
> Gus in Denver

--=20
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