MPGuino install in 94 ford ranger 4.0
 

So I got my mpguino wired up, and the speed is reading pretty close, except for one problem. The speed doesn't register on the mpguino until I'm going 15 mph or faster. I'm thinking it's the type of speed sensor I have is an issue? I've noticed my speedo in the truck bounces around a little until I get over the same speed. I know there have been similar posts here, but to be honest I don't know much about building circuit boards and I didn't quite understand the posts I saw. Can anyone help me understand if there is a way to fix my problem? I don't see how I can ever get accurate readings if this thing thinks I'm sitting still under 15 mph.

you should look at the signal from the VSS with a multimeter, or an ociloscope if you can. it should be 0 up to 5 or so then back to 0, like a switch getting turned on and off while rolling slowly. where is the VSS at on the ranger? is it a mechanical linkage to the cluster then a VSS signal generated there?

You may be able to bolt in (then wire) a later model VSS to the transfer case or transmission.