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who is averaging 50 MPG true?

Discussion in 'Gen 3 Prius Fuel Economy' started by alfon, Dec 15, 2009.

  1. SageBrush

    SageBrush Senior Member

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    A UK gallon is 20% more volume than a US gallon
     
  2. codybigdog123

    codybigdog123 Got Mad and Left in a Tizzy

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    RE: "who is averaging 50 MPG true?"

    What is true? If you mean measured by what you put in your tank, then you should realize there are a lot of errors associated with this form of measurment. An entire thread was devoted to this, and the best way to "average out" the errors, is to tabulate over 1000s of miles (ie, many fill-ups).

    All this said, I have about 4,800 miles on my GenIII, and have never gotten below 50mpg - either measured at the pump, or what's displayed by the computer (which seems to be about 2-3mpg higher than what I calculate after filling up. Since Winter, I have taken a noticable drop in mpg's from what I was getting in Augut and Sept. This is because of two reasons: (1) Winter blend gasoline and (2) Engine runs more often, and longer in colder weather. But even with this hit, I still get over 50mpg for my weekly 350-400mile comute to/from work. In August, I use to get in the high 50's. But one has to "work at it", by travelling near the speed limit, avoid rocket starts and gliding as often as possible. Best way for me to get higher MPGs is to hang out in the slow lane and go along with the flow...
     
  3. fjpod

    fjpod Member

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    I'm getting at least 50 mpg on the display...average. Sometimes 48, sometimes 53.
     
  4. 7th_paramita

    7th_paramita Junior Member

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    I wonder if your highway figures were over inflated. My highway numbers if I cruise between 75-80 are between 45 and 50 mpg at best never better than 50 (this summer). Now in the colder temperatures I have to work to stay above 40 mpg. For me it is a drop 7-8 mpg or maybe 15%. A little high but with my 6 cylinders I also had a 10% drop. Most of my driving is interstate and rural highway, and my speed is about 8 miles over speed limit (63-77).
     
  5. Megan

    Megan New Member

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    I am in So. Cal. and have been getting about 43 mpg. I drive mostly side-streets on short trips and live in a hilly area. If I can make all the green lights coming down hill, I make up for what I lose going up. However if I hit a red light and have to accelerate much, then I lose the momentum and see the result in the mpg.

    Today I did 30 miles on the freeway and reset my trip meter before leaving to see if there was a difference. I got 54.4 mpg!! Confirms for me that the lower mpg is not about the car itself, but about the nature of my routes. I just keep reminding myself that when I was driving my old car on the same routes, then I was getting MUCH less mpg than I thought!
     
  6. Bica2go

    Bica2go New Member

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    Over my last 6 tanks, I'm averaging 51.2mpg (calc'd).

    My current mpg is dropping with the cold weather (15F this morning, high of 21F and single digits expected tomorrow morning - just when I have lots of short errands to run - the perfect setup for bad mileage:(). I expect I'll be down in the 40's for the next few months.

    My Audi mpg drops about 15% in the winter so the Prius mpg drop isn't a surprise. Even my worst winter Prius mileage is double what the Audi gets and 3x what our old Ford Explorer got so I'm not complaining!
     
  7. Rhino

    Rhino New Member

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    Went to work today. Air temp 23 degrees as shown by the car. 80% highway. 27 mile commute. 51.2 mpg as shown on the dash. Eco mode. The car is totally stock. Just sharing info.
     
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  8. codybigdog123

    codybigdog123 Got Mad and Left in a Tizzy

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    This may be obvious to most, but for some it may not be -

    If you want to maximize MPGs, accelerate (as gradually as traffic will safely allow) to the desired driving speed. Then take your foot off the gas pedal (as if to glide), and then ever so gently depress the gas pedal to try and maintain speed. As much as possible (ie when driving on flat, or downhill), adjust the gas pedal to try and keep the ECO bar to the left of the center line on the display (max use of the electric motor in that region of the bar graph). If you need added power (as when going up an incline), try to minimize the time when the ECO light is off, ie, the bar is showing red (all the way to the right). What I do is try to keep the ECO light lit while going up a hill, and letting my speed drop (as long as it's not too much below the speed limit, or what the flow of traffic is doing).
     
  9. nooaah

    nooaah New Member

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    My calculated in warmer temperature (45 degrees F+) is 1-2mpg more than the display mpg. However, when it's below 40, my calculated is about 2-3 mpg below calculated. My last tank in primarily freezing temperatures showed 51.x mpg but calculated at 48.7. I'm in primarily freezing temps again but with different fuel and I'm getting 54.5mpg about 100 miles in. Difference being I'm only using Eco mode now. Highway acceleration and hills in cold temps are absolute MPG killers!
     
  10. rokibler

    rokibler Member

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    My actual average is 56.7 mpg over the life of the car, 20,418 miles. That average was measured by adding up the total gas added to the tank over its life and dividing by the mileage. The daily commute is about 22 miles over fairly flat interstate roads. Tires are set at 44/42 psi front/rear. I use the Hobbit's guidelines of keeping rpms between 1400 and 2200 whenever possible. This means very gentle acceration. I use a minimum of A/C (almost never) and heat (almost never). DC winters are fairly mild. The biggest hit on FE that I see is winter formula gas, which accounts for the plunge in MFD mpg in the graph below at about 20,000 miles. The other noticeable mpg hit occurs when forced to use the defrost during rain.
     

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  11. FireEngineer

    FireEngineer Active Member

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    My average since September 7th, around 7,500 miles ago, has been 56 MPG calculated and 62.1 MPG by the display.

    Wayne
     
  12. DetPrius

    DetPrius Active Member

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    As of my last fill up, which occurred at 6000 miles, actual lifetime mileage is at 51.2304. Most of my driving is short trip, never getting the ICE up to full temp. Mileage is dropping as expected with onset of winter and last tank was 45.21 actual mileage. That last tank of 45.21 included 3-4 hours of idling in 30-35 degree weather for heat. BTW, the Prius excels at this as I checked one time and with the OAT at 34 degrees, and the IAT set to 70, it ran for 1 minute out of every 7 minutes to maintain the IAT.
     
  13. skruse

    skruse Senior Member

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    Both our 2005 and now 2007 Prius consistently maintain 50 mpg. I use a spread sheet and keep complete records of fuel use and distance. MPG is higher in summer, lower in winter, but always around 50 mpg.
     
  14. bishoparc

    bishoparc New Member

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    I just bought my Prius on Saturday and did a lot of driving. Gas light started flashing at 465 miles. Filled up with 9.7 gallons so for this tank I averaged 47.8 MPG. That includes a 100 mile interstate trip. I'm pretty happy with that. Coming from a 2006 Nissan Pathfinder.
     
  15. GrumpyCabbie

    GrumpyCabbie Senior Member

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    Yes a UK gallon does make a difference - it's larger. A UK gallon is 4.5 litres and a US gallon is 3.9 lites. So if one of our American friends is quoting 35 mpg then it's around 42 mpg to us.

    One wonders if the trip computer in the Prius is measuring the correct mpg for the relevent country? I know mine seems to over read a little.
     
  16. Manolo1

    Manolo1 New Member

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    not me... slightly below 44 from purchase to date... only one 50.1 tank...I do mostly expressways and that is not where the Prius' is strongest...
     
  17. bibandberns

    bibandberns New Member

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    I have a 2010 prius V and get around 43 mpg. I live in the Phoenix area. It is disappointing. We do not drive it hard.
     
  18. F8L

    F8L Protecting Habitat & AG Lands

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    You should probably assess your driving patterns and adjust them so that you maximize efficiency. Driving the car hard is only one part of the mix. Short trips are nearly as bad.
     
  19. DaveinOlyWA

    DaveinOlyWA 3rd Time was Solariffic!!

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    get together with other Pri drivers in your area that also share the desire to get good mileage. you may find that your driving needs and conditions makes 43 mpg a good number.

    dont be swayed by what others report here. YMMV means exactly that and the variance very well maybe the area you are in and the routes you take. its highly unlikely to be the car
     
  20. bricor

    bricor Junior Member

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    I'm not getting 50mpg. Although my dash readout says I am. Here is my data so far. Is there some kind of calibration that should be done to the dash readout? While the mpg is okay, I'd at least like an accurate reading without having to calc it out every time. Basically, I'd like to trust the meter. Any suggestions? tks

    datedash reading milesdash reading mpgactual mpgdelta btwn reading and actual10/22/0952553.950.73.210/30/0945950.647.33.311/6/0932652.150.21.911/15/093875046.33.712/4/0943246.240.75.512/11/0939049.746.7312/22/0949951.348.72.6

    Ok, I need to learn how to post an image. I'll try again.