calculated vs. computer MPG - Please post your results

Hi All,

I hav finished 2 tanks:

Indicated Actual Indicated/Actual

60.7 58.8 1.0323
65.2 61.9 1.0533

 

I wish California had this service. It sounds so awesome! hahahaha

Maybe the next governor will abolish the self-serve gas stations. He/she would be creating jobs.

 

I've driven 45,735 miles so far in 10 months, averaging 200 miles/day on the freeway. I usually drive between 65-80 mph. I typically get 49-53 mpg and the reported mpg is usually about 1.7 miles above what I calculate from the pump and actual miles driven.

I've filled up about 90 tanks so far.

 

Just bought my 2010 Prius III yesterday- It is fabulous. So far, have driven about 300 mostly highway miles and averaging about 52 MPG! Unbelievable!

 

hello fellow priusites . is it normal to have a higher display mpg than the actual calculated ?
my past couple of fill ups ive had a .7-.9 lesser difference today the reading was 5.2 liters and after filling i calculated at 4.4 litters and similar to this a couple of days ago !!!!
prior to these readings and fill-ups i was calculating anything between ,2-.4 above,this was the first time i came in under.! i have to say i dont practice calculating to often but i like keeping tabs on what the car is doing or checking to see if my gas station is jiping me at the pump,but i do it enough to se the differences. to my experience when a car starts wasting to much gas or diesel something's wrong with the engine! :ranger:

 

enjoyable ey?!!!!!!!

 

Bought my 2010 Prius last August and just went over 20,000 miles.
I'm averaging 53.01 mpg.
The car's estimate is 55.76, about 5.1% over

 

Hi all
I'm an european Prius3 driver.
I spent some time to find out an "overall" difference of fuel consumption between calculated value and on-board computer value.
I used a german site called spritmonitor, where users have a sum of their fuel consumption, type of fuel loaded, maintenance, and much more.
So I wrote down a sheet with many averages (see file attached)

Looks like you have to add the 6,9% to the computer value to find out the real value.
That's because here in Europe Prius3 use to measure fuel consumption in l/100km. So a lower value is more optimistic than an higher one.
The opposite for US and Japan where Prius give fuel consumption in mpg or km/l, and an higher value gives better fuel economy.
I wish my Prius had a km/l value too.
Greetings

 

I've had my PriusV for 5 days and decided to fill up when I had 1/2 tank left. The computer said I got 50 mpg. I calculated it at about 45 1/2. I expect it to get better, plus we're still learning to drive it...

 

I'm always reading 0.35 L/100 km under what I'm actually calculating pen-on-paper. Sad A 4.3 L/100 km tank means I'm going to get 4.65 once I punch it into Spritmonitor.

-Iain

 

I bought my 2010 Prius on Oct 11th.

Oct 16: 1st fuel stop: 503.8 miles computer MPG: 53.6 actual MPG: 49.2 (10.231 gal)
Oct 29: 2nd fuel stop: 543.5 miles computer MPG: 58.4 actual MPG: 59.3 (9.163 gal)

 

After 14 months, 33 fill ups and 19.000km, I have an average L/100km error of 6.3% (that is, MFD gives lower L/100km values, than real).

 

353.5 miles / 7.733 gal's / indicated 47.8 /
actual 45.713 /

gas is reg with 10% Ethanol /

temps were 24-47 degrees (F) with wet
roads / rain at times.

al

 

I have a 2010 Prius, I traded in my 2006 and love this new car even more.
This summer I drove from Portland, Oregon to Nashville, Tennessee and got an amazing 54.3 mpg on the drive. This is much better than my 2006. It is now winter here and my milage is around 46 or 47 much like my 2006 model. The mpg really drops in the cold.
Stephen

 

I have a 2010 I bought in September. So far I am getting about 45-46 MPG actual. The indicated MPG is consistently about 5% higher. I live in rolling terrain and did not expect to meet the EPA mileage estimate. I'm quite happy with the mileage I'm getting so far.

 

2010 II bought about a month ago. 1400 miles total.
Filled up this morning (12/1/2010) and calculated 56.1MPG vs a displayed 59.7MPG.

 

I bought my Prius III 2010 last March and have driven about 15000 miles in Connecticut and New York.
Every time I fill the tank, I check to see how accurate the stated MPG is, and every time it is 4% off the mark. Discouraging. I have never gotten the claimed 50 mph, usually in the mid to upper 40's.

Josheyman

 

I have 2010. I originally got 48 mpg for both. Then the car had a surge issue on its own in a rain storm while I was going up a hill and now I'm getting fcd of 43 and computed (reality) 37 mpg to 31 mpg. Its been to two different dealers and they tell me that thats normal and there tests show everythings in order. They also tell me that there is a air bladder in the gas tank, so I can't go by the computed mpg, because barometric pressure will make a big difference and that gasoline has changed alot. Then I tell them how my previous prius 2007 was getting 48 pretty consistantly last winter on the same trips and was given more crap. Toyota "we care" stated 3 times that they'd get back to me and they haven't. I'm also having brake issues and the dealer couldn't find a thing wrong with those either. Toyotas great as long as your cars running good, otherwise they don't want to know you.

 

READ THIS 2010 with 8000 miles. Originally got fcd and calculated 48.6 in June. Then the car had a power surge on its own when I was going up a hill. I'm now getting 43 according to fcd and 31mpg to 37 mpg calculated. Have been to 2 dealers and they both say there's nothing wrong with the car. They say theres a air bladder in the gas tank and barometric pressure causes a big difference in fcd compared to calculated. So even though the last 8 tankfuls have produced a reality of 31 to 37 mpg that I shouldn't go by that. (What a croc of crap!) They said this is normal. I've contacted Toyota " we care " 3 times and they tell me they'll get back to me in 24 hours. Haven't heard a thing. I'm wondering if Toyota is rewarding dealers if they can lie their way out of fixing warranty issues to save them money. Also having ev problems and brake problems. Toyota cares as long as you don't have a problem!

 

My third fill-up on my 2010 IV netted me 52.4 computer mpg's, and 49.4 calculated mpg's. So far it's averaging almost 6% difference between computer and calculated, which seems what others are stating. I'm still very happy!