Does anyone else compare your MPG of your dic vs actual MPG? I'm curious as to what you are seeing. I have been getting 31mpg on the dic nearly every fill up, but when I calculate it's been 28-29mpg.

I reset the dic after every fill up and make note of:
dic mpg (around 31)
dic avg speed (40-50mph)
trip A (300 miles +/-)
gallons pumped (10 +/-)

I do mostly highway miles with cruise control set at 65-75mph.
2006 Cobalt SS/SC 2.0 (all stock)

I charted my fuel consumption on my past daily drivers, and will continue to do so with my Cobalt.

 

I did with my LNF for awhile, back when I was mostly stock (intake) and it would say 29 or 30 mpg but when i calculated i was getting 26 or 27 highway. Haven't done it since I've been tuned

 

Mine is less than 1 mpg off but that's over a lot more than 1 tank of gas.

 

So your dic is higher by 1mpg?

 

do you have any mods? unless you are completely stock i wouldnt pay attention to the dic. i am on a 2.8 m62 set up with 60# injectors plus more. i drove 3 hours highway yesterday and the dic said 38.2. got gas and did the math and actual was 29.8.

a difference of 8.4 mpg. tire size plays a role in it too.

 

My DIC said 28 and I calculated 29 the only time I checked

 

Straight city 23.7 I average 31.3 on a road trip.

 

I never calculate it. Its more fun to tell people you get 40 mpg at 75 mph in a boosted cobalt than tell them the computers wrong lol.

 

DIC seems to be pretty accurate usually.

 

I have zero mods. I haven't driven much in the past week due to the holidays/vacation. Back to work on Monday and will be checking it at the pump again....

 

Dividing the miles i drove by the gallons i put in, i get 19-22 city and 30-33 hwy

 

Yeah but I've only reset it a few times. I did notice that it gets more accurate over time. After 1 tank it might be 2-3 off. Gradually it leveled off to its current spot after a month or 2 and stayed there.

 

how do you reset the dic? and my dic shows 31-32mpg and my actual is about 28-29mpg. I let the car warm up every day, could this be why my mpg is off? I'm stock except for zzp cai.

 

Hold down the enter button until it gets cleared. You should be able to reset mpg and avg speed, maybe others, but I can't think of them off the top of my head at the moment

 

Mine was very accurate on both 93, and on E85 when I did the math with the multiplier. It may be off due to differences in tires/wheels though. The speed sensor differences between the 6 speed F40 I've got now and the F35 caused the MPG to be completely wrong now, despite fixing it in the tune.

 

I've been logging my gas since I purchased the car in December. The calculated mpg (miles / gallons at the pump) is nearly always 2mpg lower than the DIC. Usually I get about 28 calculated and 30 from the DIC. I drive nearly all highway miles and use cruise control when on the highway. I've experimented driving no more than 65mph and very conservative acceleration and also I've driven normal and it doesn't seem to make much difference.

23 tanks of gas since the beginning of December.
I usually get around 300miles to the tank and pump 10.5 gallons.
My average 28.38mpg. With my best at 30.33mpg and worst at 26.5mpg.

I do notice that when it's been cold as f^8K the mpg seem to be a little less so hopefully when it warms up I can bring my average over 30mpg.

 

For me I drive about 7 miles one way to work everyday. If I go to a fast food place during lunch its another 10 miles round trip a day. Mostly mixed driving for me at around 50-65. DIC reads about 25-27 and I calculate it to be around 22-24 so mine is on the high side a little which looks to be about average.

These figures are normal everyday driving. Doesn't seem to affect it much whether I drive like grandma or have a heavy foot and accelerate quickly.

 

With the lnf running e85, as you know, you are adjusting fuel delivery via the computer on the stock injectors. On an lsj once you throw on 60# injectors the dic reports fuel economy based on a stock injectors duty cycle, bigger injector has a lower duty cycle at the same load comparatively and reports back an inflated number.

 

Up to 26.3 in the city woot.

 

mine seems to be fairly accurate. but i don't care about a few mpg difference. i'm happy i get over 35mpg with this kind of HP.

 

If you are an LSJ, then changing injector size makes the DIC read incorrectly. It cant compensate for the different injector.

 

I do the same

 

Wait the dic is wrong???

 

The warm weather is helping my mpg a lot. I was able to hit 37mpg avg on the dic for a whole tank of gas. I've been getting upwards of 33-34mpg per tank when calculated if the weather is warm.

 

Mine is 2mpg higher than my actual. I track every fill up via GasCubby. DIC indicates 28. Actual 26-27.