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Computer tune up

Discussion in 'Gen 2 Prius Technical Discussion' started by Mikeb, Oct 17, 2008.

  1. Mikeb

    Mikeb New Member

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    My '04 Prius is getting considerably less highway MPG than 3 years ago. Do the computer settings that control the gas vs electric need to be checked for correct settings?
    Do I need to get the dealer to check the settings periodically?
    Shouldn't this be an ongoing task when I get the 5000 mile oil & filter changes.
    I've never had any mechanical or electrical problems to repair.
    Thanks for any real information about this.
     
    #1 Mikeb, Oct 17, 2008
  2. qbee42

    qbee42 My other car is a boat

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    No, there aren't any computer settings to tune up. I assume you have checked all of the obvious issues: ethanol in the gas, low tire pressure, new tires, dragging brakes, cold weather, etc.

    If everything else is okay, it is possible that your traction battery is starting to fail. When the traction (or HV) battery fails, the engine has to run a lot. One of the first signs is reduced mileage.

    How many miles do you have? Have you ever run out of gas and driven for an extended distance? Are the battery bars displaying differently than they used to?

    Tom
     
    #2 qbee42, Oct 17, 2008
  3. Mikeb

    Mikeb New Member

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    I have just less than 45k mileage.
    All of the gas here is 10% ethanol and was in 04. Keep the tires at 34-36-psi.
    Expect to get less MPG in the winter when the thermostat is calling for heat.
    Oh well, maybe I shouldn't drive as agressively.
    Thanks for the reply.
     
    #3 Mikeb, Oct 17, 2008
  4. qbee42

    qbee42 My other car is a boat

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    At 45K the battery shouldn't be an issue. It could be, but is highly unlikely.

    Driving style is likely the culprit.

    Tom
     
    #4 qbee42, Oct 17, 2008
  5. Orf

    Orf New Member

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    Mikeb, most of us on this forum are running our tyre pressures at 40/42. These pressures give much better mileage and tyre wear.
    However, if you have been running 34/36 all along this may not be your reason for low mileage, so keep looking. I suggest you up the pressures and see if this satisfies your need for better fuel economy.
     
    #5 Orf, Oct 18, 2008
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