Ok so i picked up a scan gauge the other day. Got it hooked up, filled my tank up and calibrated according to directions and followed through with the other set up instructions. All of the engine monitoring (rpm, coolant temp, etc) seem to be functioning correctly but the avg mpg and mpg are waaay out in left field. Fuel type b seems to give accurate readings when accelerating but when maintaining any speed its way off. Ive taken 2 trips 25 miles each way at 65 mph the gauge shows im getting 40 mpg ish. At 55 its even higher. While id like to see those kind of numbers, its obviously wrong. Anybody have any thoughts? I was reading about the fuel cut off, do i need to adjust this?

My current setting are. Flow Offset: 15.5% (still need to calibrate it!) Speed offset: 2% (new tires 235/85 R16)

What is you Cutoff value?