Welcome to Our Community

Wanting to join the rest of our members? Feel free to sign up today.

Sign Up

What type of Gas should Prius stay AWAY

Discussion in 'Gen III 2010+ Prius Fuel Economy' started by Hy-Bird, Dec 10, 2009.

Social Buttons

  1. Hy-Bird

    Hy-Bird Junior Member

    Joined:
    Dec 10, 2009
    Messages:
    69
    Likes Received:
    2
    Location:
    USA
    Your Vehicle Year:
    2010 Prius
    Model:
    III
    Hello this is my first time filling up my Prius (just got this 2010 Prius). I fill up with Chevron 91. Will this harm the car in anyway? I figure that is the best gas for regular cars, but not sure about the hybrid.:confused:
    1 person likes this.
  2. Paradox

    Paradox Prius Enthusiast / Moderator Staff Member

    Joined:
    Sep 22, 2005
    Messages:
    7,539
    Likes Received:
    2,429
    Location:
    N.Y.
    Your Vehicle Year:
    2014 Prius v wagon
    Model:
    Five
    Just get regular 87 octane, there is no need for plus or premium. Do not get E85 if it is available in your area as well. E10 is ok and will not harm the car.
    1 person likes this.
  3. JimboPalmer

    JimboPalmer Tsar of all the Rushers

    Joined:
    Apr 14, 2009
    Messages:
    7,628
    Likes Received:
    2,283
    Location:
    Greenwood MS USA
    Your Vehicle Year:
    2012 Prius v wagon
    Model:
    Three
    In the 2001 to 2009 Prius, no better gas mileage was measured for any gas other than the 87 octane (from a reputable station) recommended by Toyota. There is some evidence that high octane produced more power in hill climbs.

    Toyota still recommends 87 Octane for 2010. (there was a typo in early manuals that said 88, but that was an error) I have not heard that anyone has done exhaustive testing of other octanes in the new Prius.

    (In mountain areas, 85 octane is OK)
    1 person likes this.
  4. F8L

    F8L Protecting Habitat & AG Lands

    Joined:
    Aug 14, 2006
    Messages:
    18,676
    Likes Received:
    3,721
    Location:
    Sacramento, CA.
    Your Vehicle Year:
    2013 Chevy Volt
    Model:
    N/A
    You are not "treating" your car when you use higher octane fuel. In fact you could be doing more harm than good as the higher octane fuel is more resistant to burning and you may not get as complete a burn as you would with 87 octane. This would likely increase emisisons as well. The only time I would consider 91 octane on a Prius is if it had VERY high miles and required the higher octane to reduce engine pinging due to carbon deposits and such.

    Higher octane fuel will not give you more power unless your car's anti-knock sensors are reducing timing due to preignition or detonation. This can happen on some cars when under load like partial throttle freeway merging (happened on my 2000 Corvette a lot) or on smaller cars when going up steep hills.
    2 people like this.
  5. bwilson4web

    bwilson4web 03 and 10 Prius

    Joined:
    Nov 25, 2005
    Messages:
    11,930
    Likes Received:
    3,443
    Location:
    Huntsville AL with 2003 Prius
    Your Vehicle Year:
    2010 Prius
    Model:
    III
    You can see the difference between 89 and 87 octane, E10 gas in a hill climb:
    [​IMG]

    As a general rule:

    • 87 octane - appears to have more energy per unit
    • 89 octane - appears to handle very high power better
    Choose the octane that matches your driving style.

    Bob Wilson
    4 people like this.
  6. going red baby!

    going red baby! Pit Bull Lover

    Joined:
    Jul 21, 2009
    Messages:
    573
    Likes Received:
    91
    Location:
    Los Angeles
    Your Vehicle Year:
    2010 Prius
    Model:
    III


    Wow. I'm feeling really stupid because I can't understand that graph. I just woke up and am still a bit under the weather but even so... I really don't see how to get that info out of it.

    I see that it says what the blue and red lines are, but I don't know what those mean. They don't seem to represent the 87 and 89 octane. So where do you see the difference in those?

    I used to get 87 for my old truck but I filled up with 89 for my first tank thinking it would be better for my car.
  7. F8L

    F8L Protecting Habitat & AG Lands

    Joined:
    Aug 14, 2006
    Messages:
    18,676
    Likes Received:
    3,721
    Location:
    Sacramento, CA.
    Your Vehicle Year:
    2013 Chevy Volt
    Model:
    N/A


    It's not just you. It is kind of confusing because of the legend details. lol
  8. qbee42

    qbee42 My other car is a boat

    Joined:
    Mar 2, 2006
    Messages:
    18,046
    Likes Received:
    2,949
    Location:
    Northern Michigan
    Your Vehicle Year:
    2006 Prius


    In a nutshell, Bob found that 87 octane gives the best mileage, while 89 octane produces a bit more power. If you want to climb Pike's Peak in the shortest time, use 89 octane. If you want better mileage, use 87.

    As for me, I recommend 87 octane unless you are driving at altitude, in which case 85 octane is recommended.

    Tom
  9. F8L

    F8L Protecting Habitat & AG Lands

    Joined:
    Aug 14, 2006
    Messages:
    18,676
    Likes Received:
    3,721
    Location:
    Sacramento, CA.
    Your Vehicle Year:
    2013 Chevy Volt
    Model:
    N/A


    I'd be hesitant to say that it "produces a bit more power". The only real way to test that would be on a chassis or engine dyno (Dynopac or Dyno Dynamics units can simulate load characteristics) while monitoring igniting timing retard. This would allow you to determine where the extra power is coming from whether it be fuel energy content or due to an increase or decrease of ignition timing. On a properly running car you should not experience much ignition retard going up mild hills with manufacture specified octane. Since I don't think anyone has measured this in the 2010 Prius I'm not sure if this is the case and may be why Bob saw a difference between 87 and 89 octane.
  10. Hy-Bird

    Hy-Bird Junior Member

    Joined:
    Dec 10, 2009
    Messages:
    69
    Likes Received:
    2
    Location:
    USA
    Your Vehicle Year:
    2010 Prius
    Model:
    III


    I always thought the higher the gas the better it burn in the tank. So what should I do now?:confused: I just fill a tank of 91 Octane:(
  11. F8L

    F8L Protecting Habitat & AG Lands

    Joined:
    Aug 14, 2006
    Messages:
    18,676
    Likes Received:
    3,721
    Location:
    Sacramento, CA.
    Your Vehicle Year:
    2013 Chevy Volt
    Model:
    N/A


    Just drive it. It's not going to hurt anything. It's just a waste of money. :)
  12. gdbelden

    gdbelden Gator Hator

    Joined:
    May 29, 2008
    Messages:
    66
    Likes Received:
    28
    Location:
    Virginia
    Your Vehicle Year:
    2008 Prius
    Model:
    N/A
    any octane higher than what recommended in the manual for the car is just wasting money. No need for higher than the regular 87.
  13. going red baby!

    going red baby! Pit Bull Lover

    Joined:
    Jul 21, 2009
    Messages:
    573
    Likes Received:
    91
    Location:
    Los Angeles
    Your Vehicle Year:
    2010 Prius
    Model:
    III


    Get a hose and start sucking. :p ;)
  14. Hy-Bird

    Hy-Bird Junior Member

    Joined:
    Dec 10, 2009
    Messages:
    69
    Likes Received:
    2
    Location:
    USA
    Your Vehicle Year:
    2010 Prius
    Model:
    III
    OK, fellows I just called 3 Toyota dealerships and spoke to their service advisors and they all said is recommended 87 but if you put higher is ok too. You not going to feel any addition power or runs cleaners, just simply spend more $$$. I guess that answer my question too.
  15. Hy-Bird

    Hy-Bird Junior Member

    Joined:
    Dec 10, 2009
    Messages:
    69
    Likes Received:
    2
    Location:
    USA
    Your Vehicle Year:
    2010 Prius
    Model:
    III


    I like that lol :D
  16. dc202

    dc202 Member

    Joined:
    Apr 14, 2009
    Messages:
    230
    Likes Received:
    20
    Location:
    Pacific Northwest
    Your Vehicle Year:
    2010 Prius
    Model:
    III


    I am a Chevron stockholder so if you want to pay more for premium, it is OK with me:D. However, as a Prius forum member, I would highly recommend 87 octane.
  17. JimboPalmer

    JimboPalmer Tsar of all the Rushers

    Joined:
    Apr 14, 2009
    Messages:
    7,628
    Likes Received:
    2,283
    Location:
    Greenwood MS USA
    Your Vehicle Year:
    2012 Prius v wagon
    Model:
    Three


    Higher Octane fuel is good if your car 'pings', 'knocks' or suffers detonation. It is both more expensive and has slightly less energy content than lower octane fuel. Some vendors seem to put more engine cleaners in their high octane gas. (or at least they word their ads to make it appear they do)

    For this tank, you will get very slightly less MPG. Long term, use high quality 87 octane gas from busy stations.

    And the only fuels to stay away from are not gas, do not use diesel or E85 in a Prius.
  18. GreenGuy33

    GreenGuy33 Active Member

    Joined:
    Oct 18, 2009
    Messages:
    531
    Likes Received:
    28
    Location:
    Rhode Island
    Your Vehicle Year:
    2012 Prius Plug-in
    Model:
    Plug-in Base


    I thought I was reading the online dating discussion for a second.
  19. lenjack

    lenjack Member

    Joined:
    Dec 1, 2006
    Messages:
    642
    Likes Received:
    20
    Location:
    Pennsylvania USA
    Your Vehicle Year:
    2010 Prius
    Model:
    III
    There are some indications that higher than 87 octane may even be somewhat harmful to the fuel system, although using infrequently in an emergency, should be OK. 87 octane does have more energy than higher octane, and also burns more easily.
  20. qbee42

    qbee42 My other car is a boat

    Joined:
    Mar 2, 2006
    Messages:
    18,046
    Likes Received:
    2,949
    Location:
    Northern Michigan
    Your Vehicle Year:
    2006 Prius


    Me too. The first time I read that as "Get a horse and ..." :eek:

    Tom
    1 person likes this.
Similar Threads: type should
Forum Title Date
Gen III 2010+ Prius Audio and Electronics Should Type button work on Prius II 3rd Gen Stereo? Oct 19, 2011
Gen II Prius Care, Maintenance and Troubleshooting Which type of AC Compressor? Jul 11, 2014
Gen II Prius Care, Maintenance and Troubleshooting what type brake for fluid 2008 prius? Jul 1, 2014
Gen III 2010+ Prius Audio and Electronics want to upgrade prius 2012 type 2 HU to OEM type 4 or 5? May 11, 2014
Private Sales Prototype Mods Mar 27, 2014