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What Is Your WORST Prius Fuel Economy?

Discussion in 'Gen 2 Prius Fuel Economy' started by jyl, Aug 31, 2009.

  1. LightFlightDave

    LightFlightDave New Member

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    I have not really paid much attention to the tires, other than filling them to 41-42psi, the car has the stock touring wheels, and only 15k miles so I think they should be the stock touring tires but that is probably something I should double check. What are the stock 2007 touring tires supposed to be?

    I have not changed the oil yet since the dealer said he did, but I think I will do it as a precaution. I am also running whatever gas he filled it up with in Texas. As soon as it's empty I'll fill with premium.

    How can I verify the hybrid battery is in good shape?

    Mine is a 2007 touring. I just spoke to a friend that has the exact same car, he said he was getting about 37mpg at first then he learned to drive it now he gets 42mpg. It's lower than I expected but would be ok if I got it there.

    I'm trying the quick acceleration to slightly faster than I want to go, then constant. It does not seem to be improving much.

    Thanks for the tips guys,

    -Dave
     
  2. tonyrenier

    tonyrenier I grew up, but it's still red!

    Joined:
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    Location:
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    Vehicle:
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    Model:
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    I guess because my kids are grown I don't have to deal with a lot of extras. I make 3 or 4 long distance runs in the winter to see inlaws and my son in Chicago (about 200 miles). Winter, especially below 0F is the worst. I've gotten in the low 40s with me, wife and supplies for a 3-4 day stay. In town the worst I've gotten is upper 40s again below 0F. It's ranging from low 30s to mid 40s in the morning here and 50s - upper 60s in the afternoon. I'm still in the upper 50s mpg. Farewell to summer and my 60 to 70mpg.
    Tony Renier
    Green Bay, WI, USA
     
  3. ItsNotAboutTheMoney

    ItsNotAboutTheMoney EditProfOptInfoCustomUser Title

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    There are two common problems reported on PC that significantly affect mileage:
    1) overfilled oil
    2) failing 12V battery
     
  4. snead_c

    snead_c Jam Ma's Car

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    Location:
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    Vehicle:
    2013 Prius
    Model:
    Four
    Also remember that
    Owners of pre2010 Prius have a
    bladder in the gas tank that can cause wild varriations in the "calculated" milage. This is due to its size, tendancy to cut the filler pump off early and its fill capacity being changed by temperature (esp cold temps.)
    Resetting the display mpg each fill seems to give me consistently less affected numbers although some PCers report its true accuracy is off a mile or 2 per mpg reading (high, I believe. :rolleyes:)
     
  5. LightFlightDave

    LightFlightDave New Member

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    I located the description of the oil problem in another thread. I noticed the oil was overfilled. I adjusted it so it is about 20% from the top. I rotated my tires (needed it), I put exactly 42 in the front and 40 in the rear. I removed then blew out the airfilter Backwards with high pressure air but was careful not to damage it, it didn't look to bad but I will probably replace it anyway. I refilled the gas today.

    Honestly I think my biggest problem was the fact I was unaware that the first 5-15 minutes produce very bad milage, this is proving to be true. I had good number of short trips in the beggining. I've watched 5 minute segments from 50-80mpg now, my average is now at 38. I expect it will go up quickly now that I know more.

    My alignment may be the next thing to investigate, but I think I'm going to be better after tomorrow. The car is growing on me ever since I noticed much higher milage bars in the time graph. In the past couple days I've noticed the only times I get worse than 50mpg is in the first 15 minutes, and the rest of the time I'm getting 50-80mpg!! I just want to get my average closer to 50.

    I have no reason to think the 12V battery is bad. Everything on the 12V seems to work great with the exception of the smart key not always working as I think it should but it is likely because I've not read up on it yet. It's a good thought and I'll keep that in mind for when my 12V batetry does go. I'm open to check any other suggestions.

    What oil is optimal, I'm a long time user of mobile 1 synthetic, what weight is best for the Prius in an area that does not freeze?

    If I do my own oil changes and keep the receipts and use OEM toyota filters purchased at Toyota, will this void my warranty? I have had oil change places cross thread oil plugs and even not fully tighten!! I prefer to be in charge of my own oilchanges... Am I stuck buying mobile 1 and bringing it to the toyota dealer to do my changes to keep my warranty?

    Thanks everyone. I think my average is on it's way up.
     
  6. uart

    uart Senior Member

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    It's always good not to overfill the oil but I think some of the stories about large MPG drops are a bit of an exaggeration. I fill mine to right on the top level and still get 55MPG.

    Most people with a touring model Prius report slightly lower MPG than the non-touring model. The only reason that anyone has ever been able to come up with is that the tires are a little wider and chosen somewhat more for performance than efficiency.

    That sounds promising. It seems like you're getting the hang of it. Unless you're in a really cold climate you should only get poor MPG for the first 5 minutes. I generally start getting good MPG in the second 5 min interval.


    The battery is probably fine. It's easy to test the 12V battery on the prius as there's a really cool and sneaky little "maintenance mode" menu you can get into on the MFD that gives you a voltage reading. Follow the instructions in my reply #8 here : http://priuschat.com/forums/gen-ii-...conditioning-12v-aux-battery.html#post1188923

    Best oil weight is 5W30 in those conditions. Mobile 1 will be fine, as will any other name brand oil such as Valvoline, Castrol(BP), Pennzoil(Shell) or Havoline(Caltex).
     
  7. Peter_C

    Peter_C Junior Member

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    If you are not checking it with a GPS you are not getting an accurate reading. Fill the car up. Throw a GPS on the dash for a good day of driving. Then fill the car again and do the math.

    There is a way to calibrate the cars odometer so that may help. Read the manual.

    I often get around 28 towing my boat over hilly areas. 38-42 mpg is average for me and I have Scion TC wheels, which are good for a 7 mpg hit. Stock I used to get around 47 mpg over all.
     
  8. LightFlightDave

    LightFlightDave New Member

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    Not much improvement today and it was a long day of driving. I'm going to get it aligned.
     
  9. mrichards86

    mrichards86 New Member

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    Model:
    II
    I've put 9k miles on my 2007. So far, my worst tank is my current tank, because of cooler weather, 50.9/MPG halfway through my work week =)
     
  10. nyty-nyt

    nyty-nyt Member

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    Location:
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    Vehicle:
    2010 Prius
    My first tank in February's cold with the new car was 38.1 mpg, but everyting has improved steadily since; the average has been 52 mpg with my best tank being 65 mpg, all city driving.
    I just recently did my first long distance highway trip, travelling at a consistent 8 mph over the limit on cruise, about 68 mph for 450 miles and got 57 mpg, which I thought was great. I guess all those bars from the first five minutes of city driving are significant. If I could just travel at/below the limit, there would be improvement there, but I go all 'Sammy Hagar' when I think about going slowly.
     
  11. bac

    bac Active Member

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    Dave,

    What's your average commute time?

    By far, that is the largest factor in terms of fuel economy due to normal warm up time associated with all ICE autos.

    -Brad
     
  12. drash

    drash Senior Member

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    25.31 mpg during the winter. Best was 57.61. I live exactly 2 miles to work so it gets hit hard when it is parked outside then I run outside to warm it up particularly when we've had ice during the night. Next lowest tank was 33.48. Typically I'm parked in the garage and even then my lowest hovers around 42 in the winter. It's been outside for the last month (again and will be for a while :mmph: ) but surprisingly I got 50.3 mpg last tank.
     
  13. V8Cobrakid

    V8Cobrakid Green Handyman

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    while towing other vehicles and trailers used for construction purposes... i still get over 29mpg... i've NEVER seen below that.. oh wait.. i have.. 15f and bad warm ups get a little lower...