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the drop in mpg is coming!!

Discussion in 'Gen 3 Prius Main Forum' started by rxsrule, Sep 30, 2009.

  1. codybigdog123

    codybigdog123 Got Mad and Left in a Tizzy

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    "85 or lower"??

    Minimum required AKI for the Prius is 87, as per the manual. Has anybody here experienced knocking on their Prius using 87...under heavy loads/up a steep incline?
     
  2. hill

    hill High Fiber Member

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    Gee ... how surprising ... the DEPARTMENT OF AGRICULTURE says grain is efficient. Not like they don't know what side of the bread THEIR butter is on. Google ethanol an "WASTEFULL" and you'll get more articles than miles you'll be able to go on grain fuel. Here ... one of dozens of authorities that doesn't have a bias either way:

    http://hubbert.mines.edu/news/Pimentel_98-2.pdf

    Though cane suger ... switch grass show more promise than many other grains ... it's a net energy looser, bottome line.

    .
     
  3. DetPrius

    DetPrius Active Member

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    Does anyone know of a location on the web to determine when each state or region switches to the winter blend? I'd like to find out when it is for Michigan and have been googling it but no luck yet.
     
  4. Indyking

    Indyking Happy Hyundai owner...

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    The only place ethanol has worked well so far is in Brazil, where it comes from sugarcane and where I'm originally from ;).

    Brazil, a developing country, is very proud to say that due to our unprecedented advances in agroindustrial technology, we have the world's first sustainable biofuel economy!

    More here:

    [ame="http://en.wikipedia.org/wiki/Ethanol_fuel_in_Brazil"]Ethanol fuel in Brazil - Wikipedia, the free encyclopedia[/ame]
     
  5. ALS

    ALS Active Member

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    In Argentina most of the cars on the road run on natural gas due to the fact that gasoline runs $8 a gallon.
     
  6. Indyking

    Indyking Happy Hyundai owner...

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    Gasoline is not that expensive in Brazil, the reason being low demand (because most people use just etanol in their flex cars) plus Brazil has a lot of oil taken from the sea. If we import any oil at all, it is very little.
     
  7. a64pilot

    a64pilot Active Member

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    FWIW a 10% blend of ETH and gasoline should have 3.4% lower BTU per unit volume than pure gas, not 10 to 15% less. Pure Ethanol has 34% less BTU per volume than gasoline.
    Switching to high octane gas may help mileage, the reason is many states have left Premium fuel ETH free, because even though your Prius burns it just fine, many outboard motors, airplanes and other engines can't, but you wouldn't save any money as a 10% blend should only get 3% less mileage or if I do the math right your mileage should drop about 1.5 MPG if you regularly get 50 MPG, YMMV of course as always
     
  8. Sneezy

    Sneezy Member

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    10% but it's year round now, not just winter blend. I've seen a drop in all of my cars.
     
  9. john1701a

    john1701a Prius Guru

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    No, ethanol most definitely is not responsible for that. Sure, it contributes to it a drop. But my 54.1 MPG summer average using nothing but E10 (10% ethanol blend) clearly doesn't support such a drop.

    Warm-Up is by far the biggest hit to efficiency. Fortunately, Toyota made several enhancements to the system to reduce impact. The MPG hit we all see from all the winter factors won't be as big anymore.

    I'm looking forward to finding out what the difference really is... here in Minnesota.
    .
     
  10. BlueIce

    BlueIce New Member

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    If you reset the trip meter your mpg reading starts over at zero. The average mpg reading take time to climb back up. I thought this was odd after I filled up for the first time, but this is just normal. Seen this happen on each fill up. Working on my fourth tank. Average displayed MPG is reading is 53.5MPG. Make sure your tries are inflated to a pressure that matches your comfort level. Set my trie pressure at 42PSI for the front and 40PSI for the rear and the ride is just fine. Make sure the guage is working the cheap trie guages can have a several PSI error.
     
  11. rfruth

    rfruth Member

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    what really surprises me about the ethanol debate is that it enhances what the Prius does best, lower emissions and use less (crude) oil - instead there is a large group here that wants 50 + MPG even if that means lining the pockets of those that flew our own planes into our own buildings :confused:
     
  12. zonie911

    zonie911 Member

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    The same here in Tennesssee, alfon, all year long.
     
  13. fjpod

    fjpod Member

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    I believe NY uses 10% ethanol all year long as well. and I think it is in all grades.
     
  14. a64pilot

    a64pilot Active Member

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    Back in the mid 70's there were all kinds of horror stories of what was going to happen to the cars when the lead was removed from the fuel and of course catalytic converters weren't going to last but a couple of thousand miles and cost thousands to replace, emission controls will not work, kill mileage and be a maintenance nightmare, etc. etc.
    Probably the best thing to happen to automobiles in a long time was the removal of lead. Now that the lead is gone, you can have 10,000 miles between oil changes and spark plugs last more than 100,000 miles.
    Maybe Ethanol will be a similar situation. Eventually the engines may be re-designed to use ethanol and it's advantages and maybe we will like it then.
    Doesn't matter really, because you have no choice, usually.
     
  15. Old Bald Guy

    Old Bald Guy Old Bald Guy

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    A friend has a flex fuel pickup (that means he can run the fuel with 85% alky). On ordinary 10% alky fuel ... which is the normal mix required by law ... he gets 17 NPG. On the 85% alky fuel ... he gets 11 MPG.

    As a former pro mechanic, I know that alcohol does not and cannot give the mileage of gasoline. So tell me then, how does a 36% drop in mileage (17 down to 11) equal a benefit for anyone ... other than the alky makers?

    As to your comment about it being efficient to produce alky from corn (which it isn"t) ... why not then use sugar beets ... which are producing 3 times as much alky per acre as corn ... in Mexico and other places?
     
  16. capek

    capek New Member

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    Interesting OP. I'm getting a little less MPG on my last fill-up a few weeks ago (4-5 MPG less), and I thought it was just that I was driving it in a little different way. This could explain it though, I guess.
     
  17. Zhentar

    Zhentar New Member

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    You're comparing apples & oranges. Gallons is a measure of volume, nothing else. The change is in miles per gallon of fuel, not of gasoline. Your miles per gallon of gasoline has actually increased, because less of your fuel is gasoline. With that E85, your miles per gallon of fuel is way down, but you need 6.7 gallons of fuel to contain 1 gallon of gasoline- meaning you're actually getting 73 miles per gallon of gasoline.

    Comparing MPG for pure gasoline to E10 or E85 is no more accurate than comparing it to Diesel. They're different fuels, with different energy densities; comparing volume does not give any weight to the efficiency of the combustion, the cost of the fuel, the environmental impact, nor any other aspect aside from the range of a vehicle given a certain space requirement.
     
  18. Zhentar

    Zhentar New Member

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    Sorry for the confusion there; the Prius minimum AKI is 87 at sea level; I'm from Colorado where the higher altitude & thinner air means 85 AKI is as good as or better than 87 AKI at sea level.

    You aren't likely to hear the Prius, nor any other modern engine, knock as ECUs can accommodate for low AKI fuel.
     
  19. RodJo

    RodJo Member

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    I'm guessing that they are not counting the oil used to make the fertilizers or the natural gas used to convert corn into ethanol.
     
  20. PriusCrazy

    PriusCrazy Blizzard Pearl for Me

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    Hmmm... You might be onto something. Let me try some numbers here. :popcorn:

    Assuming:
    10% ethanol = 10% less mpg

    on a 10 gallon tank, that would equate to 1 gallon of gas "lost".

    Wouldn't that mean you have to buy 10% more gas if it's 10% enriched?

    Maybe the environmental issues are a plus, but it seems the "less consumption of evil oil" theory doesn't hold; you end up having to buy the same amount of "evil oil" to travel the same distance.