calculated vs. computer MPG - Please post your results

Discussion in 'Gen 3 Prius Fuel Economy' started by F8L, Jul 10, 2009.

  1. bdc101

    bdc101 Member

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    First tank: dash says 41.0, actually came out as 42.5.

    Second tank: Dash says 44.1, actually came out as 41.3.

    Both were topped off. Total average is 41.8 since I bought the car and fixed the HG.

    The second fill may have been a little bit more topped off. Either way, I am spending about $5/week on gas, so I feel pretty great. (Coming from driving a 2003 BMW X5 gas guzzler.)

    I am getting a set of snow tires later today and taking it on its first highway road trip since I bought it and fixed the head gasket. Looking forward to having a long trip under its belt and seeing the highway mileage.
     
    ASRDogman likes this.
  2. Mendel Leisk

    Mendel Leisk MMX GEN III

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    What was the miles on it? Have you also cleaned the EGR circuit?
     
  3. bdc101

    bdc101 Member

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    I am at 263k now, and yes I had it cleaned in the ultrasonic tank until it was sparkly.
     
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  4. Outdoors68

    Outdoors68 Junior Member

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    At 246k and average around 45-46mph still, a nice tailwind and some back country roads and I can hit that 50mph they talk about;)
     
  5. Bill Norton

    Bill Norton Senior Member

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    "it" ?
    Which parts did you clean?
    The intake manifold is the important part because it is the part that makes the individual port flow uneven.
     
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  6. wezzdc

    wezzdc New Member

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    I'm only getting 30-35mpg even with conservative driving habits. Could this be an indicator of a bad battery? How else can I troubleshoot this issue.
     
  7. Mendel Leisk

    Mendel Leisk MMX GEN III

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    Calculated or displayed? For how long, recent drop? What’s the miles on it? Any recent maintenance, or new tires? Change to driving patterns, trip length, conditions, speed?

    addendum: just noticed your other posting, regarding hitting a curb, air bags deployed and so on. Seriously, you’ve got major fish to fry, and need pro to assess.
     
    #1327 Mendel Leisk, Nov 26, 2025 at 8:42 AM
    Last edited: Nov 26, 2025 at 9:02 AM