fuel flow sensing

[Clare Snyder]

>Larry,
>
>On Sun, 14 Sep 1997, Lawrence S. Harris III wrote:
>
>> is done on a line labeled DOL (Data output link).  The computer also has 
>> an input from the VSS (Vehicle Speed Sensor) and can thus calculate MPG.
>
>Do you know how the Vehicle Speed Sensor works? I am currently working on
>a system that uses magnets fixed onto the drive shaft, and a hall effect
>transistor. The problem i have found is that the shaft tends to move
>around quite a bit (in relation to the rest of the vehicle). As i have
>mounted the hall effect device onto the underside of the car, it
>sometimese cannot sense the magnet becaues the drive shaft is too far
>away. I haven't had a second attempt yet (with longer magnets/stronger and
>moving the hall effect device closer) but i was wondering if there is
>some other way that i should maybe try.
>
>Thanks
>
>Jason
>
>
Get the unit that fits on the speedo gear, and the speedo cable fastens to
it. Common on many cars with standard mechanical speedos and cruise or
engine management systems. If necessary, I can find out at least oneunit
that may work - let me know what kind of car/tranny.>