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What is your trip mpg on short drives? Gen 4

Discussion in 'Gen 4 Prius Fuel Economy' started by Higgins909, Sep 10, 2021.

  1. fuzzy1

    fuzzy1 Senior Member

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    Longer distances do average in more different conditions, so a law of averages does kick in.

    For a single cold start trip, with a Trip meter reset, the engine warmup fuel penalty is mostly paid in the first couple minutes. Plus the energy cost of accelerating the car from rest to highway speed. So at a couple miles, the displayed MPG is horrid. But the longer the trip, the more good-MPG miles get averaged in with the initial horrid miles, and the displayed figure should asymptotically rise towards what the car can achieve on a fully warmed engine at steady highway speed.

    For another exercise, reset a Trip meter again after the engine has warmed and the car is up to steady highway speed. If you are on flat ground without a strong headwind, it should immediately display a higher number, similar to what the meter can display on long trips.

    For a couple more exercises, reset the Trip meter while climbing a hill, then again while descending. The first should quickly show a fairly low MPG, due to the extra fuel burn needed to climb. The later should show a sky-high number, as the car effortlessly glides down a hill with little or no fuel.

    For extra credit, do the same exercise on flat ground with head- and tail-winds.
     
  2. Doug McC

    Doug McC Active Member

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    Am I missing something in this discussion or is my 2022 Prius Nightshade XLE the only Prius that has current trip mpg available, not Trip A or Trip B, but a “trip” that begins when I turn the car on and ends when it is turned off? In other words, I can easily get 199.9mpg just by turning the car on in the garage to check something and never letting the ice kick in. Useless info, but doable. FWTW
     
  3. dbstoo

    dbstoo Senior Member

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    There is a button labeled "trip" near your left thumb. Each time you press it the display will change from ODO through various trip settings.
     
    Doug McC likes this.
  4. Doug McC

    Doug McC Active Member

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    YEP!
     
  5. Ryder99

    Ryder99 Member

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    I have been keeping track of indicated mpg and miles/gallons and have seen from 1 to 5 mpg difference. So while the indicated mpg is close, but the divided method is closer. I don't bother with the air temp, desity of the air, and the fuel temp and density along with engine temp...