Anybody know what this extra plug is for? Also, my Edge doesn't seem to display the correct speed. I have adjust for my tire size and my gearing but is still pretty far off. At 75mph the Edge shows 82mph.

EDIT: Nevermind. Just called Edge. I guess that small plug is for diesel applications.

 

If it's showing a speed that doesn't sound right, I would double check your settings for tires and gear ratio. Mine is right where it should be according to those portable radar systems on route 17 lol and the speedometer is about 4-7mph fast after hitting 45mph.

 

^^check that you are following the instructions and saving your settings correctly. My corrected settings for rear end ratio and larger than stock tires match up exactly...speedo and Gryphon (Edge) mph.

Now mpG is a different story. Programmer always says I'm getting 2 MPG better than reality. Great for advertising I suppose, but an outright lie. I read on some forum that the F-150 PCMs are all about the extra 2 mpg lie, but I have no idea of the true origins.

 

When I spoke to the Edge tech, he said that it should be no more than 4 mph off. I tried measuring the tire with a tape measure to get the exact diameter, then computing for the circumference, and it was still off. I guess I will just have to play around with the settings until I find the one that is closest.