The vertical axis of the FUEL MAP is engine load based on airflow reading from the AFM, so the map point will always travel down diagonally to the right as the RPM increases under throttle and the airflow increases. The numbers in the cells are hexadecimal, as its based on a binary computer, where you count from 0 to 15 instead of 0 to 9 as you do in decimal. As you cant have 10 as a hexadecimal number it becomes A to F as you get above 9. Easiest thing to do is use a hex to decimal converter off the web if you cant think in hex. So 0 to FF in hex works out as 0 to 255 in decimal, which is the number of fuel steps you have from no fuel, to maximum at 255. This number basically controls the injector opening time.
So the AFM is the primary input for engine load? How does the ECU use the throttle pot input?
The throttle pot is only there to show the throttle is shut / open for idle control and if it changes value rapidly as you floor the throttle the ECU is programmed to add fuel enrichment, nothing more.
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