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Any harm in filling with 91 gas?

Discussion in 'Gen 3 Prius Main Forum' started by macmaster05, Apr 18, 2019.

  1. macmaster05

    macmaster05 Senor Member

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    I was at the Costco gas station last night to refill and apparently they had issues with their regular gas earlier in the day, so they were only giving out Premium fuel for the regular price ($3.80). The gas attendant kept telling everyone how great of a deal it was for us. I filled it anyway but it worries me that I didn’t see any other Priuses at the time. Is there actually any mechanical reason why filling with Premium might be bad for a Prius?
     
  2. hill

    hill High Fiber Member

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    It's fine ...
    .
     
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  3. ETC(SS)

    ETC(SS) The OTHER One Percenter.....

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    +1

    Putting higher octane fuel in the car will not help the car, but it will not hurt it either.
     
  4. TMR-JWAP

    TMR-JWAP Senior Member

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    Higher octane=more resistant to detonation/preignition
    more resistant to detonation due to having slower flame front propagation
    slower flame front propagation actually = potentially less power (oddly enough), unless the car is designed for higher octanes (ie..higher compression, timing, etc)

    Will it hurt anything to use a higher octane than recommended by manufacturer? Only your wallet in most circumstances, but not yours this time.
     
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  5. Mendel Leisk

    Mendel Leisk Senior Member

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  6. hill

    hill High Fiber Member

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    If it helps carry this thread evem more ad nauseam;

    the only thing I can imagine adding is this - ever since 2007, many cars began having the ability to alter timing to allow for higher & lower octane. We had the hybrid Lexus SUV in 2006 and it had this feature which allowed us to use any grade. Yes there would be minuscule loss of efficiency with low-grade, but it still ran FINE -
    FINE ... see post #2

    .
     
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  7. macmaster05

    macmaster05 Senor Member

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    Thank you everyone
     
  8. orenji

    orenji Senior Member

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    I would be more concern with Costco brand! Who knows what rebranded brand it is and what additive is added if any to keep the engine clean!
     
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  9. hill

    hill High Fiber Member

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    that's what Chevron wants you to believe.
    7 things to know before you buy gas at Costco Wholesale - Clark Howard

    .
     
    #9 hill, Apr 18, 2019
    Last edited: Apr 18, 2019
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  10. TMR-JWAP

    TMR-JWAP Senior Member

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    regular price ($3.80).

    Now I feel bad. I was just complaining to the wife yesterday about how the price of gas has gone up so much recently.
    $2.54...............
    Guess I'll stop complaining..
     
  11. Mendel Leisk

    Mendel Leisk Senior Member

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    We're currently at $1.70 (CDN) per liter. Doing the math, around $4.80 US per (US) gallon. It is pretty much an all-time high I think, hopefully will subside soon.
     
  12. ETC(SS)

    ETC(SS) The OTHER One Percenter.....

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    Yeah...but you guys up there are, like, saving the whole planet----right? :p
     
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  13. orenji

    orenji Senior Member

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    Just because it’s Top Teir per government regulations does not mean it has enough additives needed to really keep an engine clean. 8 of the top Automakers stated that most Top Tier Gas meets government standards but not theirs. Chevron is one of the best fuels one can buy.
     
  14. orenji

    orenji Senior Member

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    We are over $5.00 in Los Angeles
     
  15. will the engineer

    will the engineer Active Member

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    FML!
     
  16. fuzzy1

    fuzzy1 Senior Member

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    So who is selling gasoline that doesn't meet government standards? And why haven't they been shut down and penalized?
     
  17. Mendel Leisk

    Mendel Leisk Senior Member

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    Dropped a dime a liter, across town, now $1.60 (CDN). All boats going up and down with the tide...
     
  18. fuzzy1

    fuzzy1 Senior Member

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    Our tide is only rising right now:
    upload_2019-4-18_22-10-1.png
    ... while at least one of your localities seems to have a 'pulse and glide' pattern:
    upload_2019-4-18_22-12-33.png

    That pattern isn't BC-wide. Victoria has a 'pulse then hang tight' pattern, while Vancouver and BC overall are messier.
     
  19. orenji

    orenji Senior Member

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    They do meet government standards, which is a minimum amount of additives to meet the standards. Where some brands (Chevron) exceed the minimum standards.
     
  20. fuzzy1

    fuzzy1 Senior Member

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    Then just what did you mean by "most Top Tier Gas meets government standards" back at post #13? And why would 'Top Tier' even exist if it was not higher than government standards?
     
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