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Fluctuating average MPG on display

Discussion in 'Gen 2 Prius Fuel Economy' started by jjensen, May 22, 2005.

  1. jjensen

    jjensen New Member

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    Am on about my 6th tank of gas. After the last two fillups, the average mpg on the consumption display greatly fluctuates and doesn't "settle down" until about 50 miles on the tank. I didn't notice this until the last two fillups. My driving habits have not changed. Is this normal? Does anyone else have this problem?
     
    #1 jjensen, May 22, 2005
  2. kidtwist

    kidtwist New Member

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    If you're talking about what I think you are, then yes it's normal.
    It fluctuates because you have a smaller body of data at first on which to calculate an average. The fluctuations should diminish as you put on miles.
     
    #2 kidtwist, May 22, 2005
  3. gschoen

    gschoen Member

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    It's because it's an average of all your miles. When you first fillup, you have almost no miles so each change makes a big difference. As you drive more, bad mileage for 1-2 miles doesn't have so much of an impact once say 300 miles are already recorded.

    Think of anything else averaged over time, your GPA, batting averages, etc. etc.
     
    #3 gschoen, May 22, 2005
  4. Tideland Prius

    Tideland Prius Moderator of the North
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    :iagree
     
    #4 Tideland Prius, May 22, 2005
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