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Big drop in 2005 gas mileage??

Discussion in 'Gen 2 Prius Audio and Electronics' started by ctwallace, Oct 1, 2007.

  1. ctwallace

    ctwallace New Member

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    My 2005 Prius was getting 40-45mpg for in city driving. All at once it dropped to 30-35mpg and has stayed at that the last two months. Dealer couldn't find any problem, said to keep tire pressure at 41, which has had no effect. It only has 45,000 miles on it. I can't find anyone who seems to know what the problem is or how to fix it.
     
  2. Frank Hudon

    Frank Hudon Senior Member

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    a couple of possibilities
    1) air filter plugged
    2) a change of gas stations to one pumping E10 or E20
    3) change of route that has more hills or construction or any thing to slow your average speed down
    4) more use of A/C like a lowered temp setting
    just some things to look at

    Edit: when you check the air filter you want to take it out and look at the bottom as that is the side that gets dirty.
     
  3. Winston

    Winston Member

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    May 19, 2007
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    Location:
    SF Bay Area, California
    Vehicle:
    2007 Prius
    Number one way to tell if something is wrong with your car is if the gas mileage has dropped. You should not be getting 30-35 unless you... well... I cant think of anything that would cause your mileage to be that low. Unless all of your trips are 1-2 miles long. Even when I am in heavy stop and go traffic I get 45-50 mpg.

    Couple other items not on Franks list could be the coolant thermostat, or bad spark plugs.

    Tell us a little more about your driving. What mileage do you get when you are out on the freeway, with the car warmed up cruising at 60mph with the cruise control? You should see around 50-55mpg in that scenario. Have you done any mileage tests in specific conditions?
     
  4. jayeeegee

    jayeeegee New Member

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    Aug 31, 2006
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    Location:
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    Vehicle:
    2005 Prius
    Hi CT. I have the same problem with my 2005. Overall average since purchase is 48 mpg. Now getting high 30's. I know it's winter but I've gone through 5 previous winters WITHOUT this problem. My biggest concern is ethanol. Ohio now let's stations add up to 10% without any notice. A phone call to a UDF manager should know said all brands were now 10%. There are different state rules regarding posting, e.g Florida requires posting ANY ethanol on the pump. Michigan is same as Ohio. Google topic to find your state. This could very well be a new "TAX" courtesy of the liberals. Regards, John