Hey Mike what unit is it that you use that shows your GPH and mph and mpg and everything, as we all know the factory read out is far from accurate and all Ive been doing is hand calculating all along.
-Jordan-
That is a ScanGauge II (
www.scangauge.com)...
ScanGauge II you have to calibrate to the GPH and Speed sensors of the truck to get proper readings. Because believe it or not ScanGauge II uses only those 2 values.
Speed (MPH) / Flow (GPH) = MPG
55 MPH / 2.30 GPH = 23.9 MPG
So how did I get it calibrated?
Simple... Use a GPS and set the offset of speed on the SGII. Mine is 1% off.
Then as for the GPH offset. You have to fill up at a fuel station let the pump click off by itself don't top off the tank. Then drive thru 3/4 of tank and return back to the very same pump in the same direction. Fill up again the same way. Now the SGII will report the gallons use its see now you adjust the offset to match the gallons on the pump. Once done leave it alone. Don't have to do this over and over again.
Like on my truck speed is 1% off and GPH is 24% off.
Like on Mom's 96 speed is 0% off and GPH is 233% off.
I've used it during the period my fuel sender died as a fuel gauge so I would run out of fuel. The funny part was it was really close to being dead on everytime. Reason why its not... Because I found out from weights and measures there is a small amount of error allowed in the pumps so getting fuel at one spot might give you a bit more where another might not.
My numbers are closer to correct on the SGII because my odometer on the dash is off by 0.5 MPH so in a tank of fuel the odometer is off by about 15-20 Miles...