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Fuel cost calculations

Discussion in 'Gen 3 Prius Main Forum' started by BZzap!, Feb 28, 2016.

  1. BZzap!

    BZzap! Senior Member

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    Does anyone know if fuel cost calculations are averaged automatically if you fill up a partial tank at a different cost??Say that you fill up your tank at the half way mark with fuel costing 20% higher than the previous fuel stop. Does the computer then recalculate the FULL tank of fuel at the currently price point or does it average it out?
     
    sfky likes this.
  2. Virg

    Virg Junior Member

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    No it does not. You can change the cost per gallon of fuel by using the "trip" buttons on the steering wheel when you fill up; right after you start the car after a fill up. You must do this within about five seconds after pushing the power button.
     
  3. BZzap!

    BZzap! Senior Member

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    Yes, I do understand the reset procedure but was just wondering if the fuel cost calculations were averaged with what is left in the tank. Thanks for the reply, none the less.
     
  4. daddyd302

    daddyd302 Junior Member

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    First off, the Prius isn't as high tech as you wish it could be. What you're asking, the Prius is too dumb to calculate that.

    In addition to what Virg says, the MPG on the Prius is pretty dumb. Do not trust it to give you your MPG. For example it'll say I'm averaging 48 MPG and when I fill up and do the math myself, it's 43 MPG or other times 45 MPG. It's always off by 3-6 MPG. It's always best to fill all the way, otherwise it'll be tricky to calculate your MPG.

    If you can figure out what your MPG is, you'll be able to estimate how many miles you can drive before you need to fill up. I usually fill up around 450 miles. I will usually have about 2 gallons left but I do it anyways to be safe.

    I use gasbuddy to calculate my fuel cost. Some people on here use fuelly.

    GasBuddy.com - Find Low Gas Prices in the USA and Canada

    Fuelly - Track and Compare your MPG
     
    #4 daddyd302, Mar 2, 2016
    Last edited: Mar 2, 2016
  5. VovCA

    VovCA Member

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    May be I need setup $1 per gallon, then it is easy scalable.
     
  6. 348

    348 Junior Member

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    The only way to accurately calculate your fuel consumption is some simple math after you fill up.
     
  7. FuelMiser

    FuelMiser Senior Member

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    I would say NO. It simply uses the current fuel price (from the last time you set it) and the fuel used on that trip to calculate the fuel cost for that trip.
     
  8. BZzap!

    BZzap! Senior Member

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    I do have a ScanGauge on board that I programmed to read the fuel level. Maybe I'll see if it has that capability. I guess I'm picking the fly specks out of the pepper.
    Thanks for your spot-on reply.
     
  9. Oskar

    Oskar Member

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    I've found this to be pretty much standard. I've owned my Prius for about a year and a half (bought it new) and consistently, since the day I drove it off the lot, there has been a difference of between 3 and 5 gallons from the Prius mpg and the calculated one I do. What is interesting is that the readout from the Prius is always higher. ;)