Reprogramming fuel tank MPG (miles to empty feature) - Forscan

[Gary Waugh]

Okay peeps, I just invested in an ODB2 USB reader and installed forscan on my computer and it all seems to work. So for my first trick I want to fix a minor naggle that has upsett me for the last 10 years, and I am hoping someone on here can help.

My expedition averages something around 14 MPG, and has done all its life (130,000+ miles) but every time I refill the gas tank it tells me I have 500+ miles to empty! I have never managed more than about 350 miles out of a tank so the computer must be using some preset MPG number to make the calculation. Is it possible with forscan to reprogram the value used to be more realistic? This is a 2008 Limited EL.

Thanks for any suggestions..

Gary

 

[07xln]

So when you're on E does it say you can still go 150 miles?

 

[J Ski]

Okay peeps, I just invested in an ODB2 USB reader and installed forscan on my computer and it all seems to work. So for my first trick I want to fix a minor naggle that has upsett me for the last 10 years, and I am hoping someone on here can help.

My expedition averages something around 14 MPG, and has done all its life (130,000+ miles) but every time I refill the gas tank it tells me I have 500+ miles to empty! I have never managed more than about 350 miles out of a tank so the computer must be using some preset MPG number to make the calculation. Is it possible with forscan to reprogram the value used to be more realistic? This is a 2008 Limited EL.

Thanks for any suggestions..

Gary

Same issue. I have a lifted 2016 Platinum el that gets roughly 14 city and 19 highway. Fill ups usually show me 470-510 miles to empty. Start driving in the city, stop and go, untuned with a k&n intake system and 35s and that number quickly drops. Watch the miles to empty number while using odometer reading to drive exactly one mile and I lose more than 1 mile off my “miles to empty” reading. Hop on the highway doing 63 (sweet spot) and I can get almost 2-3 miles by the odometer before I lose 1 mile of the “miles to empty” reading. All depends on your driving style. I’d say your truck is fine. I’m at about 400 miles when I fill up with like 1/8 of a tank left. I don’t always trust that portion of the computer system especially the gas gauge bc you can top it off too much and possibly cause the gas level indicator to be off. I’m goi g to change plugs soon and get a tube so hopefully that will help my mpg

 

[Gary Waugh]

the miles to empty drops linearly as the tank empties and by the time I arrive at empty it is giving something close to 0 miles left so the level gauge is correct, just the conversion factor to convert gallons to miles (MPG) seems to be wrong.. I would love it to just use my actual average MPG (14.3) or let me program a realistic value (it seems to be using something like 20mpg for the calculation!!).

Gary

 

[Michael Shepherd]

Based on experiences with the 2007 Ford Freestyle that the Expedition replaced, I suspect the issue has to do with usable fuel versus actual capacity of the tank. With our Freestyle after a fill-up, the info center would indicate 465 miles to empty, but we rarely managed more than 360 miles between fill-ups on the highway. The vehicle purportedly had a 19 gallon fuel tank, but even with the info center indicating only 10 miles to empty, I was never able to add more than 16.7 gallons when refueling, which made me think there was 1-2 gallons of unusable fuel due to the shape of the tank and positioning of the fuel sump(s).

 

[Gary Waugh]

I think my car (2008 EL expedition) has a 30 gallon tank and when I fill up I regularly get 28 or 29 gallons in it.. Don't know what the computer thinks the tank holds, as you say maybe that number is wrong, can the tank capacity or the MPG used for the calculation be reprogrammed with the forscan software?

Gary

 

[AllBoostNoEco]

I think my car (2008 EL expedition) has a 30 gallon tank and when I fill up I regularly get 28 or 29 gallons in it.. Don't know what the computer thinks the tank holds, as you say maybe that number is wrong, can the tank capacity or the MPG used for the calculation be reprogrammed with the forscan software?

Gary

I have never seen any listings for the MPG readout in any of the FORScan spreadsheets I’ve looked at. It could exist, and just hasn’t been found yet. If you park up or downhill and artificially increase or decrease the fuel level, does the DTE change accordingly? I ask because my driveway has a 20-degree slope, but if I park overnight, the DTE is the same even though it shows an extra 1/8th of a tank.
My 2015 changes the miles to empty based on the average from the last time I filled up, and it’s always about 0.5 MPG less than the actual average. I’ve seen as low as 440 DTE and as high as 620. Hence no reason to dig into it.