refuled then reset trip A and B, drove off and they are all different mpg's, A reading 5 mpg higher

Discussion in 'Gen 3 Prius Fuel Economy' started by priustexasbob, Feb 21, 2018.

  1. priustexasbob

    priustexasbob Member

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    I refuled, reset trip A and B, went back to at start and drove away. I circled around from start to A then to B, they all read different start and B were close, about 1 or 2 mpg difference but A was off by 5 mpg. I figured they would be pretty much the same reading but why A was so much off was perplexing. I arrived at gym about 5 miles away, the difference from A to B was down to 4 mpg. why so much disparity? should they all not be about the same?
     
    #1 priustexasbob, Feb 21, 2018
  2. Mendel Leisk

    Mendel Leisk Senior Member

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    Going with just the text I've made bold: yeah I don't understand either, would think they should be the same. But: you completely lost me in the part that isn't highlighted.
     
    #2 Mendel Leisk, Feb 21, 2018
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  3. Threej

    Threej Member

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    Like Mendel, I'm having difficulty reading the details of your procedure.

    However--
    In the first 30 seconds of a cold startup, my Prius drinks gas like a drunkard. If I started my prius, immediately reset trip A, and then took about 15 seconds to switch over and reset trip B, the amount of gas burned on trip A but not trip B in those 15 seconds would be noticeable, and would probably take a little bit more than 5 miles to average out.
     
    #3 Threej, Feb 21, 2018
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  4. bisco

    bisco cookie crumbler

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    try the same 20 mile drive twice, after the car is fully warmed, and see how they compare. keep the same speed and acceleration as much as possible, the human factor and wind are the outliers.
     
    #4 bisco, Feb 21, 2018
  5. priustexasbob

    priustexasbob Member

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    ok. the car was already warmed up and I refuled. after refueling I started the car and BEFORE moving even one foot, I reset both trip meters. then as I was driving I kept switching between the trip meters.
     
    #5 priustexasbob, Feb 23, 2018
  6. priustexasbob

    priustexasbob Member

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    oh man I fell like a dumbbunny - this was meant for the C chat which is what I own. I'm going to copy it there too or a mod can move it.
     
    #6 priustexasbob, Feb 25, 2018
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