Something wrong with my Prius II - It takes more gas than it advertised.

Discussion in 'Gen 3 Prius Fuel Economy' started by hschen, Aug 24, 2009.

  1. bestmapman

    bestmapman 04, 07 ,08, 09, 10, 16, 21 Prime

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    I had the same feelings and observations when I first got the Prius. Here is my advice.

    Study
    Learn
    Practice

    Study. Find the threads mentioned here and find everything you can on the car. Attend meet-ups and find as much info as you can.

    Learn. Watch what other people are saying and see what is working for them. Attend a clinic and get some experience both on line and in person

    Practice. Put your knowledge to use. Refine your techniques and start posting you accomplishments. Attend a fuel economy challenge. You will learn a lot of valuable lessons there.
     
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  2. hschen

    hschen New Member

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    -- Friday Update --

    Ave mpg rised from 58.8 of yesterday morning to 59.5 as of this morning. Gas tank is 3 bars left. It's getting more difficult to climb up mpg for obvious reason. But I think by the end of the tank, I should be able to reach my goal of 60 mpg.
     
  3. cpatch

    cpatch New Member

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    Check out this thread:

    http://priuschat.com/forums/gen-iii...oll-what-mpg-you-getting-in-your-gen-3-a.html

    You'll notice that 26% of the respondents are, like you, getting 45-50 mpg (7% are getting less). 75% are getting 55 mpg or less, so the higher numbers are rare. (For that matter, 35% of the 2010 Priuses being tracked at fueleconomy.gov are also getting 50 mpg or less as are a whopping 75% of those being tracked at fuelly.com.)
     
  4. Codyroo

    Codyroo Senior Member

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    The only potential downside is that when you fill it up and compare it to your hand calculation, you will probably be disappointed since it appears that the MFD gas mileage reading tends to be higher than the hand calculated gas mileage.

    Of course, no one is going to require you to do the hand calculation, therefore when people ask you what kind of mileage you get, you can honestly tell them what the MFD tells you.

    :D
     
  5. hschen

    hschen New Member

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    Codyroo, thx for your reminder. I am mentally prepared.
    In fact my first tank, the error was only 0.5 mpg.
     
  6. PriusRoadWarrior

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    Make sure your not in "B" mode
     
  7. hschen

    hschen New Member

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    What's B mode?

    BTW, -- Update --

    I finished my 2nd tank with an average of 59.5 mpg. Too bad I did not achieve 60 mpg as expected. Refilled last night (3rd tank), drove home and commuted back to office this morning, the round trip of commute on I-405 I got 62.7 mpg and I started to drive more normally (accelerate more aggressively).
     
  8. statultra

    statultra uber-Senior Member

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    the only advice i have, is to drive it like a normal car, you sometimes end up getting good mileage, while enjoying the cruise to work.

    in my 05 prius i average 51 mpg consistently, driving it like a normal car, accelerating fairly hard also
     
  9. PeteJE

    PeteJE Junior Member

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    It sounds like your are handily beating the EPA and thus your original post title seems null and void.

    I am getting what the EPA suggests... 46 - 50 when I have lots of short drives, local errands and such (under 10 mile round trip). For my work commute, I can consistently get mid 50s. My longer term average is right at 51 currently.

    Sometimes I try hard at getting good mileage, other times I drive normally, which, for me includes accelerations into the pwr area. In general, the car is retraining how I drive and I like it. This still is a lot of fun and the most payoff in a car purchase I can remember for myself.
     
  10. hschen

    hschen New Member

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    Thanks for your comment, PeteJE.
    This thread and title is a story/journey of me from a newbie in hybrid to a convinced/confident hybrid driver. Hope this thread can help more people like me who was new in the hybrid world.
    I just returned from a round trip from LA to LV on I-15. On the trip I used power mode and normal mode when necessary for speed pick up and long hill climbing. Driving mostly at 75-80 mph, I still got over 50 mpg (~ 50.6 mpg), displayed mpg of course. Now I am not afraid to use power mode anymore. In fact I found it's more efficient to use the power mode to quickly get up to the speed and then cruise using normal or ECO mode. Staying in ECO all the time will frastrate you and others on the high speed freeway.


     
  11. cmalberto

    cmalberto New Member

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    Good to hear. I am taking my first 400 mile trip this weekend, through Houston and San Antonio down to Del Rio. Looking forward to see how "she" will respond.

    --Mickey
     
  12. jburns

    jburns Senior Senior Member

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    We make to much of a big deal out of the different modes.There is no reason staying in ECO mode should frustrate you or anyone else on the road. The same amount of power is available in all modes. The only difference is how far you have to push the gas pedal down to reach full power.
     
  13. midcow2

    midcow2 2023 Prius LE Supersonic Red

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    A couple of things:

    (1) break-in .. mentioned before
    (2) even with a CD (coefficient of drag) of a very low .25 you have to remember that air resistance goes upwith the square of the MPH. You will get your best mPG at 50-55, less at 60-65, and much less at 80. At 80 are encountering a large amount of wind resistance which severely impacts your mileage.
    (3) If you want to get really good Mileage, you have to completley rethink your way of driving. slow starts, anticipate lights, minimize acceleration, reduce you highway speed, use ECO mode ( lower power).
    (4). Mileage varies with weather conditions. if you are encountering cold weather; it could lower your mileage.
    (5) check the air pressure of your tires; a little over the recommended will give you better milage and will not adversely affect the handling.

    In spite of all the above, you are actually getting pretty good mileage..... is you want better then it is up to you ;)

    Good luck!
     
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  14. hschen

    hschen New Member

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    I don't think so. I personally has not, but my wife did experience this when she drove up a very long and steep hill, in ECO mode Prius ran out of power (slow down and continued to slow down) even she floored the accelerator. She called me then and asked for help. I told her to use power mode. She said the car picked up the speed immediately. I think in ECO mode the computer limits engine and motor RPM or transmission ratio. Only power mode eliminates the restrictions.
    Someone know better shall say something.
     
  15. a64pilot

    a64pilot Active Member

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    If your right, it's easy to verify. Do a couple of 0 to 60 runs in ECO, average the time followed by a couple in power, average the times and see how much difference there is. Interested to see what the results are.
     
  16. qbee42

    qbee42 My other car is a boat

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    The same power is available in all modes. The Prius chief engineer personally told us this in Detroit. Your wife may have run out of power going uphill, but it wasn't because of ECO mode; the same would have happened in any mode.

    Tom
     
  17. qbee42

    qbee42 My other car is a boat

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    If you do this test, make sure to return the SOC to the same level before each run, otherwise the results will be useless.

    Tom
     
  18. a64pilot

    a64pilot Active Member

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    Your right of course. I have never done a 0 to 60 run in my Prius, so I didn't think of that. Probably want a couple of min. cruise time to allow temps of everything to normalize between runs anyway.
     
  19. bwilson4web

    bwilson4web BMW i3 and Model 3

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    This is interesting. Can you provide the longitude and latitude of the hill and direction on the road? This will give me an idea of the hill characteristics. Locally, I have an 8.3% grade hill, 525 ft. tall, 1.2 miles long. But there are some larger hills with different grades within 30-45 minutes from Huntsville. I would like to see if I can find something to replicate her results.

    Is it possible she had driven at relatively low speeds, say 25-30 mph for a while before driving up the hill? The reason is I'm finding at speeds below 46 mph, the car cycles the traction battery more and more as the speeds decrease. About half and hour at say 30 mph, and the traction battery SOC will be below half. I'm speculating that the traction battery SOC may have been low before approaching the base of the hill.

    Thanks,
    Bob Wilson
     
  20. hschen

    hschen New Member

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    Well, I should believe what Toyota's Chief Engineer said. Perhaps it's a mental thing. Perhaps my dear wife didn't floor the pedal in ECO mode and thus didn't get the full power. But in power mode, the same pedal position generated considerable more power. I will confirm with her.
    To answer bwilson4web's question about the long hill. It's CA-241, a toll highway (privately owned I heard) connecting CA-91 to Irvine area.