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2012 Prius MPG gauge

Discussion in 'Gen 3 Prius Fuel Economy' started by alfon, Feb 17, 2012.

  1. alfon

    alfon Senior Member

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    If you have a 2012 model year Prius let us know
    if the MPG gauge is accurate or if its over reading like the
    2010, and 2011 model years are by about 3 - 3.5 mpg.

    I have read that the 2012 Prius C model the gauge when tested
    by Wayne Gerdes of Cleanmpg.com, was within 1% accurate.

    So, I am just wondering if the 2012 Prius has more accurate software in the system.

    alfon
     
  2. Paradox

    Paradox Prius Enthusiast / Moderator
    Staff Member

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    Yes, we were told by Toyota at the press event last year that the 2012's will have a more accurate gauge.
     
    1 person likes this.
  3. skm009

    skm009 Member

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    I only have data from two fill-ups and so far it looks like they are off by almost 7%. I know that sample is too small here but will continue to update as I get more data.

    Tank 1

    45.7(Calculated)
    48.7(MFD)
    MFD off by 6.56%

    Tank 2

    46.2(Calculated)
    49.6(MFD)
    MFD off by 7.35%
     
    3 people like this.
  4. Zanrok

    Zanrok Casual Prius Lover

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    Vehicle:
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    II
    I have 3 fill ups so far and I confirm that the gauge is off still.

    For example...
    Tank 1
    54.4 (MFD)
    51.4 (Calculated)

    Tank 2
    54.2 (MFD)
    51.0 (Calculated)

    Tank 3
    56.4 (MFD)
    52.8 (Calculated)

    Hope that helps.
     
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  5. poshunl

    poshunl New Member

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    Five
    Prius v 5, 2012
    Tank 2 over a 264 mile freeway round trip. Average speed 70mph

    37.84(Calculated)
    41.9(MFD)
    MFD off by 9.68%
     
  6. alfon

    alfon Senior Member

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    Looks like the truth is in and Toyota
    did not upgrade the Prius V and regular Prius
    mpg gauge softwareto to reflect a more accurate reading.

    But, according to Wayne Gerdes, when he tested the new
    Prius C and filled up to the top of the tank, where
    you can see the gas, than drove about 60 miles round
    trip and filled up again at the same gas station and same pump
    right up to the neck again the mpg was just about
    on the money between calculated and indicated.

    I believe it was about 85 mpg.
     
  7. skm009

    skm009 Member

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    Dang! I thought I was going to hit the magic number 50 with this tank. Below are the details.

    Tank 3

    49.5(Calculated)
    53.3(MFD)
    MFD off by 7.67%
     
  8. Scott196250

    Scott196250 ScottnATL

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    That should be an easy software fix . . .yet it still isnt fixed. Hence, I conclude that Toyota wishes the software to remain exactly as it is. Why? So that those Prius owners who are NOT as A-R about tracking their mileage as we are will continue to feel good about their purchase and brag to their friends about their (slightly inflated) MPH.

    No?
     
  9. skm009

    skm009 Member

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    I totally agree that's the ulterior motive.
     
  10. SuperchargedMR2

    SuperchargedMR2 Diehard Rams Fan

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    +1

    I would say that's exactly the real truth. :mad:
     
  11. cproaudio

    cproaudio Speedlock Overrider

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    hmm 7% seems to be the magic number. If PiP has the same margin of error, when CONS reads 200mpg, it's actually 186mpg. Way to go Toyota.
     
  12. Zanrok

    Zanrok Casual Prius Lover

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    kind of aggravating... especially if its accurate in the C. =/
     
  13. jack520

    jack520 Member

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    Plug-in Base
    My numbers are 46.3 actual, 49.8 on the trip computer on my second tank...