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sudden low mpg

Discussion in 'Gen 2 Prius Fuel Economy' started by joycebasch, Aug 11, 2005.

  1. joycebasch

    joycebasch New Member

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    My Prius 2001 had a small battery failure. (Not the large, warrantied battery.) At a toyota dealership,Ii bought a new small battery. For the second time, something connectd with the fuel system was changed as identified by corporate Toyota.

    Now, two months later and after my 60,000 mile service, the car is getting very low mpg. Before this service, it was getting 42 - 44 mpg.
    Now, it's consistently getting only 38-40 mpg.

    When checked on the computer at Toyota, all looks good. I'm the only driver and my destinations and style of driving haven't changed. Any suggestions what I can do to increase my mpg?
     
    #1 joycebasch, Aug 11, 2005
  2. wstander

    wstander New Member

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    Have you verified tire pressures after the 2 service periods? I found sometimes well-meaning techs 'adjust' tire pressure; a few times the 'new' pressure was 8 lbs too low (guage mis-read?)

    )Keep in mind, at the high MPG numbers we enjoy, a 4 mpg shift is about 10%. If we were used to 20mpg on another car, +/_ 2mpg would not seem bad, but yet that is 10% also.)

    Are all other parameters the same? Are you using the A/C more in these warmer months?
     
    #2 wstander, Aug 11, 2005
  3. joycebasch

    joycebasch New Member

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    thanx for the suggestions but........

    Yes, I have checked the tire pressure since I found that I got better mpg with 35 pounds. The tire pressure was always at 35 or a little higher, probably because of the heat in southern CA.
    I am not using the air conditioning more than i have
    been.
    when I filled the car with gas, this week, the indicator showed 48 -49 mpg for a short time.
    It has NEVER been that high since I bought the car
    new in jan. 2001. The highest the mpg has ever
    been has been 45-46.......... and not consistently.
     
    #3 joycebasch, Aug 12, 2005
  4. efusco

    efusco Moderator Emeritus
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    Ok, I'm confused. Is your mileage higher or lower now?
     
    #4 efusco, Aug 12, 2005
  5. joycebasch

    joycebasch New Member

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    Mileagae is lots lower.
    And it was a sudden lowering. It did not diminish gradually.

    I wrote to find out if others have experienced the
    same thing!
     
    #5 joycebasch, Aug 12, 2005
  6. efusco

    efusco Moderator Emeritus
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    Ok, I was confused by the following statement which seems to suggest that you're getting significantly higher mileage.

    While it's possible that something is wrong, I'd give it a couple tanks of gas and confirm you mileage by hand. Even one bad day or a trip along a different route can lower your mileage enough to have an impact on the end-of-tank mpg. I realize you've had the car a long time and respect that you know when something is wrong so I don't wanna blow you off, but, as others have pointed out, the drop is very small on a percentage basis.

    Things to check... Did they use the wrong oil at your last service? Could the alignment be off? You said you already checked the tires and that would have been my first suggestion...all my 'sudden drops' have been due to a tire going flat. Could the parking brake be on slightly creating some drag?
     
    #6 efusco, Aug 12, 2005
  7. efusco

    efusco Moderator Emeritus
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    BTW, does your paperwork specify what was changed, exactly, with the fuel system? If not, call your service manager and find out...TSB or SSC number and or just the exact part that was replaced. That could certainly contribute.
     
    #7 efusco, Aug 12, 2005
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