Walt, On the fuel sending unit, you should take one apart sometime. It works on the rheostat principal, just a little different design then other sending units. And on the oil sending unit. You've got the principle and idea of how it works right, it's just the values you've got are incorrect. Marty In a message dated 9/22/00 10:46:46 PM Central Daylight Time, Whalt@xxxx writes: << The fuel sending unit isn't that easy. It's not a rheostat like what is used on many other cars. Instead it is a free floating thing that somehow works by solid state. I've never taken one apart to find out. >>