1. Attachments are working again! Check out this thread for more details and to report any other bugs.

Wintertime premium gas?

Discussion in 'Gen 2 Prius Fuel Economy' started by acausedelle, Feb 13, 2013.

  1. acausedelle

    acausedelle Hypermiling Through Campus

    Joined:
    Jan 18, 2013
    14
    4
    0
    Location:
    Green Lake, Wisconsin
    Vehicle:
    2005 Prius
    Model:
    N/A
    I read a lot of the articles about how premium gas isn't the best gas for the prius. What caught my eye was when users on this site were talking about how ethanol is worse for the engine, and how ethanol is not good for gas mileage. I also think that there are differences in the gas around the US and the world. I live in Wisconsin, so it's very cold. Most of the gas stations around here have ethanol mixed in for regular and mid-grade, but the premium doesn't have any ethanol added.

    Reasons why NOT to use PREMIUM GAS in your Prius | PriusChat

    That was the article I was looking at, and explains about the sticker saying that it contains ethanol. That's not the case around here, and it sparked my interest. More specifically:

    "To achieve higher octane, premium has a larger percentage of ethanol. If you look on the pump at the gas station, there is a sticker saying that it can contain up to 10% ethanol. Ethanol provides less mileage and collects condensation water more than gas without or with a lower precentage of ethanol in the mix."

    Any input? Are the levels of ethanol different in certain areas of the US?
     
  2. KK6PD

    KK6PD _ . _ . / _ _ . _

    Joined:
    Mar 24, 2008
    4,003
    944
    118
    Location:
    Los Angeles Foothills
    Vehicle:
    Other Hybrid
    Model:
    N/A
    AFIK, every Prius owners manual states use 87 Octane only.
    To do otherwise is wasting money!
    Maybe it's just me!

    BTW we are waiting on the "Summer Blend", gas here in L.A.
    I drove by my Shell station, today 87 Regular was $4.199!
    I am at 3 pips now and will have the recall work done on steering and ECU pump done Friday.
    I may give it to them with 1 pip
    Shell is 2 blocks away! :)
     
  3. wjtracy

    wjtracy Senior Member

    Joined:
    Sep 19, 2006
    11,309
    3,586
    1
    Location:
    Northern VA (NoVA)
    Vehicle:
    Other Hybrid
    Model:
    N/A
    Ethanol is considered safe additive, the only downside being slight loss in MPG (which of course Prius drivers hate that, but there is no harm to the car). All octane grades of gasoline can be made with or without ethanol, but many of us are forced to use 10% ethanol which is mandated by EPA in most urban and suburban areas. I have never had a problem with accidental fills of Premium in the Prius, but some references say Premium could cause problems starting engine. Midgrade should be fine. Regular is recommended. Most of us feel Regular is best and if 0% ethanol is available it's OK, but if you are paying more than about 10 cents a gallon extra for the 0% ethanol, you are not saving money. There is a webpage that gives 0% ethanol availability. Most of us would not use Premium even if it had 0% ethanol, as the extra $$ would not be worth it.
     
    uart likes this.
  4. Mendel Leisk

    Mendel Leisk Senior Member

    Joined:
    Oct 17, 2010
    54,470
    38,103
    80
    Location:
    Greater Vancouver, British Columbia, Canada
    Vehicle:
    2010 Prius
    Model:
    Touring
    In Canada, in my area anyway, Chevron has stickers on all their pumps saying "may contain up to 10% ethanol". Except their highest grade, which says "does not contain ethanol". I'm likely paraphrasing a bit, but that's gist of it.

    I'd love to try some ethanol free, but just seems a bit much to have to purchase uselessly high octane gas to get it. Maybe I will some time just to see if it does anything for mileage, performance, whatever.
     
  5. uart

    uart Senior Member

    Joined:
    Sep 7, 2009
    4,215
    1,200
    0
    Location:
    Australia
    Vehicle:
    2005 Prius
    We can get "regular" petrol (gas) here with or without 10% ethanol (though E10 is the most commonly available).

    I get better fuel economy with the non ethanol variety, but the difference is only marginal. It varies a bit from time to time and where I fill up, but generally only about 2 to 4 percent difference. So yeah, if you've got to pay more than about 4 or 5 percent extra for the non ethanol gas then it may not be worthwhile.
     
  6. enviroprius

    enviroprius Junior Member

    Joined:
    Nov 16, 2006
    91
    12
    0
    Location:
    Sonoma, CA
    Vehicle:
    2007 Prius
    Model:
    N/A
    I've been using mid-grade for the past 5-6 fill ups because I noticed the engine pinging under heavy load. No problems with it. Runs super quiet now. Anyone else experience the pinging?
     
    Corwyn likes this.
  7. cwerdna

    cwerdna Senior Member

    Joined:
    Sep 4, 2005
    12,544
    2,122
    1
    Location:
    SF Bay Area, CA
    Vehicle:
    2006 Prius
    During the summer, I have noticed some pinging on my 06 w/regular CA gas and usually end up running midgrade or premium, which definitely helps.

    In the winter, I definitely have no probs w/pinging on regular, likely due to the colder weather.
     
  8. mmmodem

    mmmodem Senior Taste Tester

    Joined:
    Nov 17, 2011
    2,732
    1,703
    0
    Location:
    Bay Area, CA
    Vehicle:
    2012 Prius Plug-in
    Model:
    Plug-in Base
    Ethanol has less energy per unit than gasoline so it gets you slightly less fuel economy. If price were the same, obviously, go for non ethanol. Ethanol also has detrimental effects on some engine components at high enough concentrations. The EPA says 10% E10 is safe for use in all cars.

    Prius is designed to run on 87 octane gas. If you put premium in, you don't get any benefits except better fuel economy vs regular E10 gas. Is the extra fuel economy worth the 20 cent price per gallon premium? Theoretically, no. You can always do a test trial, though.
     
  9. enviroprius

    enviroprius Junior Member

    Joined:
    Nov 16, 2006
    91
    12
    0
    Location:
    Sonoma, CA
    Vehicle:
    2007 Prius
    Model:
    N/A
    Thanks! Next tank I'll try going back. It was warmer when I switched to 89.
     
  10. Mendel Leisk

    Mendel Leisk Senior Member

    Joined:
    Oct 17, 2010
    54,470
    38,103
    80
    Location:
    Greater Vancouver, British Columbia, Canada
    Vehicle:
    2010 Prius
    Model:
    Touring
    I've heard engines with higher miles can be more ping-prone because of carbon build-up in the cylinder head. This carbon does a couple of things: increases compression ratio (the carbon occupies part of the former air volume) and provides hot spots that might pre-ignite portions of the gas-air mix.
     
  11. dbcassidy

    dbcassidy Toyota Hybrid Nation, 8 Million Strong

    Joined:
    May 13, 2008
    1,581
    290
    3
    Location:
    Middlesex County, MA
    Vehicle:
    2008 Prius
    Model:
    Two
    Ethanol is one of those things that get worse over time sitting in your gas tank unused. It will separate and attract and hold moisture. However, with the tank bladder, this should be a non-issue. Mpg do take a slight hit, but I find in the Prius it is not that substantial. Other vehicles with a conventional fuel tank run a higher probability of moisture related issues w/ ethanol. Condensation in the tank from teamperature changes (warm to cold), humidity in the air can add to the moisture build up. Fuel conditioner is recommended.

    Just my .02 cents,

    DBCassidy
     
  12. KK6PD

    KK6PD _ . _ . / _ _ . _

    Joined:
    Mar 24, 2008
    4,003
    944
    118
    Location:
    Los Angeles Foothills
    Vehicle:
    Other Hybrid
    Model:
    N/A
    So I got the recalls done, going back Monday because steering wheel is no longer straight, I even pointed this out,.Grrrr
    When I did fill up gas had gone up a dime to $4.299, big GRRRRR!
     
  13. Tommytoes

    Tommytoes Junior Member

    Joined:
    Mar 16, 2013
    5
    0
    0
    Location:
    Central Florida
    Vehicle:
    2005 Prius
    Model:
    II
    A word of caution when using additives. Prius manual says not to use methanal, and some additives have methanol.
    Some if not most also use ethanol to absorb moisture, but this would presumably put you above the 10% mix. For more information go here: Review of Gas Treatment & Fuel Additive Products - Alcohol Content

    Toodles
     
  14. Rest

    Rest Active Member

    Joined:
    Aug 13, 2005
    1,210
    51
    2
    Location:
    CA
    Vehicle:
    2007 Prius
    Premium isn't the best gas for any vehicle unless the engine was designed to run on it, performance and mileage will suffer.
     
  15. Data Daedalus

    Data Daedalus Senior Member

    Joined:
    Jul 6, 2013
    1,022
    1,182
    0
    Location:
    Wembley, London
    Vehicle:
    2008 Prius
    Model:
    II
    While I totally agree that Premium (Super) Unleaded Fuel isn't the best gas for the Prius, is there any truth that running a tankful won't harm the engine (apart from reduced MPG and performance), but will definitely clean out the injectors? I'm talking about trying a tankful of Shell Nitro+ V-Power. I ran this fuel and it's previous incarnations in my old Mazda MX-3 1.6i DOHC for the 8.5 years that I owned it - largely because that car didn't like regular gas - and it ran silky smooth on Premium. It also had excellent cleaning additives that kept my engine clean. I don't want to run my Prius T Spirit on expensive premium gas anyway, but would one tank of high octane fuel cause it harm in anyway?
     
  16. dbcassidy

    dbcassidy Toyota Hybrid Nation, 8 Million Strong

    Joined:
    May 13, 2008
    1,581
    290
    3
    Location:
    Middlesex County, MA
    Vehicle:
    2008 Prius
    Model:
    Two
    There lies the problem with ethanol it is a water magnet. Given a little time that water/ethanol/ gaso mix turns into a corrosive mix witch can raise havoc in injectors, fuel pumps and carbs.

    Seen and repaired/ replaced many of the above due to this corrosion.

    DBCassidy
     
  17. wjtracy

    wjtracy Senior Member

    Joined:
    Sep 19, 2006
    11,309
    3,586
    1
    Location:
    Northern VA (NoVA)
    Vehicle:
    Other Hybrid
    Model:
    N/A
    According to one Prius maintenance book I have, it says Premium could cause hard staring problems. But mostly I expect you can run premium with no issues. We don't have too many folks here using premium for clean out because our regular has additives too. Not sure about London.
     
  18. Data Daedalus

    Data Daedalus Senior Member

    Joined:
    Jul 6, 2013
    1,022
    1,182
    0
    Location:
    Wembley, London
    Vehicle:
    2008 Prius
    Model:
    II
    Thank you WJTracy, in that case I won't. Our regular fuels over here in London / UK also have cleaning additives - of Shell's Regular, of that I am pretty certain. I'll just stick with regular petrol over here :)
     
  19. elpoverito

    elpoverito New Member

    Joined:
    Nov 22, 2013
    1
    1
    0
    Vehicle:
    2012 Prius
    Model:
    III
    YES, but the best is still to cut-off the head of a 5 month virgin chicken and spread the blood on the back seat, not only it will clean the injectors, but it will clean water pump !
     
    Data Daedalus likes this.
  20. N.J.PRIUS

    N.J.PRIUS Member

    Joined:
    Mar 23, 2011
    139
    49
    0
    Location:
    Fort Lee, NJ
    Vehicle:
    2013 Prius Plug-in
    Model:
    Plug-in Advanced
    Here in N.J. I haven't seen prices below $3.00 for a long long time. Prices had been falling and suddenly about a week or so ago they started going back up in a big way. I found a station selling for $2.97 and filled up! That same station is now selling for $3.15.