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bad mpg

Discussion in 'Gen 2 Prius Main Forum' started by stylinnnn, Sep 12, 2019.

  1. stylinnnn

    stylinnnn Junior Member

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    I know many in a poker group I belong too are getting 50, 52, 55,
    sad I only get 47 mpg.
    I 've never had over 50 mpg ever.
    I know many will say that is normal
    but I had 5 other cars same gen 2, and ALL got over 53 mpg.
    Ideas. thanks
     
    #1 stylinnnn, Sep 12, 2019
    Last edited: Sep 12, 2019
  2. Skibob

    Skibob Senior Member

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    Post in the Gen 2 fuel mileage section?
     
  3. bisco

    bisco cookie crumbler

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    there's no such thing as the same gen 2, and the older they get, the more they differ as things clog and wear. how many miles on her?
     
  4. stylinnnn

    stylinnnn Junior Member

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    The other cars were 06 models with 280k average and got over 52 mpg easy and the one now is 09 with 120 k and never gets over ..50 mpg
     
  5. bisco

    bisco cookie crumbler

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    have you checked the 12v health? hybrid battery?

    tires? oil? air filter? plugs?
     
  6. PriusCamper

    PriusCamper Senior Member

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    Fastest way to boost MPG is to boost tire pressure... Add a couple few pounds of air per tire until you notice the first loss in traction and then back it off a little. I prefer 47psi in front and 45psi in rear. The boost in gas mileage is huge from just this alone.
     
  7. TMR-JWAP

    TMR-JWAP Senior Member

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    Stylin..

    at 47 mpg, it's just not worth worrying about. If you see a big change, then I would be concerned. The difference between 52-53ish and 47 is merely running the AC more, or a few short trips. Maybe their commute is at a steady 40 mph and your's is up and down? There's so many very small variables that can make (what seems to be) a large difference once you get near 50mpg. I've been paying more attention to technique recently, and my last 3 tanks have all been >54 mpg. My current tank is at 325 miles, still has 5 dots on the screen and 56.2 mpg showing on MFD. I do a 22 mile commute each way in about 28 minutes. About half is 45ish and half 64ish mph. I know, without a doubt, if I ran my AC like my son does, I would be around 46-47.

    Although I also have to state my current HV battery is built with modules from a low mile Gen 4 wreck, so that may also have some effect on the mpg.

    With just a nothing special HV battery and driving like I stole it I was always 44-48 mpg in this car.
     
  8. stylinnnn

    stylinnnn Junior Member

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    My older cars got better mileage. I 've have never got over 50 mpg ever though and I am not used to that. I am not talking about a few trips I am talking about many trips. According the many here with the a/c on you get worse, but I have refined my cruising technique and actually get more with the a/c on.
     
  9. TMR-JWAP

    TMR-JWAP Senior Member

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    Fill us in, I'm all ears. I'd like to hear about it.
     
  10. jb in NE

    jb in NE Senior Member

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    Is this compared to running with the windows open for ventilation, or to running with windows closed and no A/C running?
     
  11. mpg_numbers_guy

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    Your comment makes no sense. The energy to run the AC is not free. You can't compare a different driving style with the AC on and call it more efficient. Please stop misleading people on here.
     
  12. Moving Right Along

    Moving Right Along Senior Member

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    Driving style, distance, and location all play into fuel efficiency, and don’t forget how the fuel bladder will expand or contract differently on different cars. 47 miles per gallon is absolutely normal. According to Fuelly, the average MPG of a gen 2 Prius is between 43-44 based on the thousands of samples they have. Your friends could have higher MPG because they drive slower, they drive more on highways or more long distances at a time, or they inflated their tires more or just got lucky that their cars are naturally a bit more efficient, or a combination of these.
     
  13. jb in NE

    jb in NE Senior Member

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    This will not affect the amount of fuel consumed by the engine. It may affect the calculated miles per gallon for an individual tank fill, but over a number of fills any tank size variations should be insignificant.
     
  14. oil_burner

    oil_burner Active Member

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    do the math on the difference in your wallet each fill up at 47 vs 50mpg and you'll quickly realize who cares.
     
  15. Prius92

    Prius92 Member

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    Exactly. At an average 12k miles per year, the difference of 5mpg is about $9 per month.

    I don't know how the hell you people can have so much air in your tires. I'm at 40 in the front and it is terrible in Iowa roads.

    The TC light comes on hitting a bump because of the traction loss at one tire from making the tires so firm.

    BTW..why does the 3rd gen Prius call for tire inflation the same around all 4 wheels and the 2nd gen is different between front and back?
     
  16. mpg_numbers_guy

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    I don't know how you notice a difference. :D Can't tell the difference with 50 PSI in the Prius, and on my old Civic I ran 68 PSI with no notice. 80 PSI in my tiny Insight is noticeable, but that's because it's crazy high PSI on a 1800lb car. 40 PSI on any car shouldn't even be noticeable unless the car only weighs 1000lbs.
     
  17. fuzzy1

    fuzzy1 Senior Member

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    It doesn't. 35F/33R for the normal 15" wheels, something lower but still different for the 17" wheels.
     
  18. Prius92

    Prius92 Member

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    Well part of the issue may be in the still factory original front struts that are 11 years old with 129k miles.

    ...80 PSI? I don't know of any passenger car tire that can take that on the sidewall.
     
  19. oil_burner

    oil_burner Active Member

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    I don't know how you don't notice. unless your roads are glass smooth, any city with pot holes and frost heaves, expansion joints etc. 30 PSI is a blissful thump while 50psi is BANG BANG BANG. But if you can tolerate or not notice the difference, then ignorance is bliss.

    My wife is the same way, she rides in my Miata and I ask her if she notices a difference compared to my truck. The Miata is lowered on very stiff coil overs, low profile tires, and I have solid poly engine mounts, a racing clutch. Driving that thing gives me a migraine after 20 minutes if I don't wear earplugs and my kidneys hurt over every railroad crossing. She doesn't even notice.
     
  20. mpg_numbers_guy

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    Michigan's toads are not glass smooth. :D I wish they were!

    When I first inflated my Insight's tires to 60 PSI vs the 35 PSI they were at when I bought the car, I did notice a difference on gravel roads only. It was the first time I had noticed any difference due to tire inflation, but then again we're talking about an unusually rough gravel road, and high PSI in a super lightweight car. Overtime I got used to it, so I don't really notice it now, but before driving the Insight I never noticed it on larger cars. I suppose it depends on the person, as you said. Going from 60 PSI to 80 PSI didn't seem change the ride quality at all.