Ford Powerstroke Diesel Forum banner

DIC fuel data inaccuracies

2K views 13 replies 6 participants last post by  Arhaifa 
#1 ·
Miles to empty and gallons consumed per the DIC are really inaccurate. The other day I had this scenario:

20 miles to empty
20.1 gallons consumed
AVG 15.2 mpg
Fuel gauge read more than 1/8 of a tank remaining

The truck took 22.2 gallons of diesel to fill it. Basically, the DIC is telling me I'm about to run empty--when I really have almost four gallons remaining. Add to that, the DIC claims that only 20.1 gallons were consumed. The only thing accurate is the fuel gauge. Anyone else having these inaccuracies, and can this be reset to be a little more reliable? As it is right now, the information off of the DIC is pretty useless. Please let me know if you uave any insights. Thanks.
 
#2 ·
25-22.2=2.8 gallons, not almost four gallons. So really your DIC is off about 2.8-1.3= 1.5 gallons. Maybe its a reserve?

I have noticed the DIC is off about 1 gallon in my truck per fillup. But my fillups are 30+ gallons. This in turn makes my MPG average off by a little, but not much.
 
#3 ·
It is a 26 gallon tank. So his 3.8 is close to 4 gallons.

Mine will off 0.5 to 1 gallon at each fill up. 2 gallons off seems a lot.
 
#5 ·
You'r right it is 26 gallons, wonder why everyone thinks they are 25 including myself. Still way to small IMO!

I wonder if my 35" tires could have an impact.
I don't see how it could have an impact on your gallons used. It will however give you a wrong average MPG, as you are actually going slightly further then it says.

You can go to the dealer, and have them correct your speedo for tires up to 34.8", this will also give you better average MPG readouts.
 
#6 ·
Hi, on a side note: how happy are you with your tires? I am looking at getting the toyo AT2 myself and was after peoples opinions.
My mileage seems accurate enough with regards to fill ups. I think that they program the fuel sensors to err on the side of caution. I've got a longbox and think the tank is 35 gallon [ as well as a 90 gallon transfer tank for long trips ]
 
#10 ·
It's 37.5 gallon on the long bed and I have run mine empty and have first hand knowledge of that.

I find that my Fuel Used in the Trip-o-meter display is really accurate to what fuel I have used. It's rarely off by more than 1/2 gallon when I fuel up.
 
#11 ·
:agree: my first fillup ever my DIC said 15 miles till empty and 36 gallons used. I put 36.5 gallons in.
 
#12 ·
Strange difference

hello, I also find a strange difference between the DIC and what my edge insigt cts shows. For instance at 100kmh -around 60mph- DIC shows 9 l/100km and the edge shows 6 l/100km. Of course the edge seems very optimistic as an F350 6.7 is not a Prius. Anyway 9 l/100km is not so bad but I can't explain the difference as both are picking their information from the very same source. Edge being plugged to the OBDII. Any ideas? Thanks.
 
#13 ·
hello, I also find a strange difference between the DIC and what my edge insigt cts shows. For instance at 100kmh -around 60mph- DIC shows 9 l/100km and the edge shows 6 l/100km. Of course the edge seems very optimistic as an F350 6.7 is not a Prius. Anyway 9 l/100km is not so bad but I can't explain the difference as both are picking their information from the very same source. Edge being plugged to the OBDII. Any ideas? Thanks.
Do you have your gear ratio and tire size set correctly with the edge? If you have 4.10's and 33" tires but you edge thinks you have 3.55's and 37" tires then you're going to be way off! Hope this helps.
 
#14 ·
Edge's computer allows me to enter tire size but not gear ratio. Anyway it's more for the speedometer to be correct in case you don't run stock tyres. I tried to put my stock size and it changed nothing. Again it's strange as both DIC and Edge are linked to the engine's computer and its sensors. But give different results...
Thanks for your help anyway,
 
This is an older thread, you may not receive a response, and could be reviving an old thread. Please consider creating a new thread.
Top