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Sudden drop in mpg

Discussion in 'Gen 4 Prius Fuel Economy' started by momto4girls, Jun 17, 2018.

  1. Starship16

    Starship16 Senior Member

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    I don't think it's really starting over. Like I said, it jumps right back up to where it was after just a few minutes. But to be honest, I drive so little, the gas mileage is not really that important. Just checking the trip A mileage is fine.

    Did anyone solve mom's question?

    Thanks Mendel. I do shut off the AC for awhile before I get home. Open the vents, open the windows, get everything fresh again. It gets pretty darn hot here, on Pluto. :eek:
     
    #21 Starship16, Jun 17, 2018
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  2. krmcg

    krmcg Lowered Blizzard Pearl Beauty

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    I've never reset my "B" trip meter and it has lifetime numbers. It does not reset at 10,000 miles - just cannot display that 10,000 digit.
    I reset trip "A" and the eco screen each fillup and keep track of those numbers on an excel spreadsheet. 51 fillups to date.
     
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  3. momto4girls

    momto4girls Junior Member

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    Thanks for all the suggestions. I'm in Alabama, so AC is a non negotiable. ;) But I didn't experience this last summer--otherwise I would chalk it up to AC use. I'm going to read my manual and look at resetting trip a or b next time I fill up.

    I know there are many factors that can affect mpg, so I may never know. Of all the factors you all listed--there's nothing that jumps out at me like, "oh, that's probably it". Nothing about my driving habits or routes has changed. Oil change was 4000 miles ago. Hopefully it's just a glitch and will return to normal soon. Last summer I took the car from B'ham, AL to Anna Maria, FL loaded with suitcases, beach gear, and 2 passengers, AC running the whole time, and I still averaged 58 mpg.
     
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  4. Starship16

    Starship16 Senior Member

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    I did my monthly tire pressure check first thing this morning, Each tire was 2 psi below the required level. (Should have known-- the dealer never gets it right.) Even with that, I still got 56.6 mpg after 600 miles. (My calculation, not the computer.)

    Mom, are you driving in Eco mode? Checked the tire pressure recently? I agree with you about the AC. I use it daily. A few months ago, I had the same strange drop in mpg as you. Never did find out why.

    Just another Prius oddity....
     
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  5. Andyprius1

    Andyprius1 Senior Member

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    2 is not a catastrophe, unless you start too low. I always fill to 50lbs and then when the pressure gets to recommend, say 35, then I get the Low Pressure warning and can still fill at my leisure.
     
  6. Starship16

    Starship16 Senior Member

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    Now days, I keep my tire psi right at the factory recommended level. I no longer experiment with those high pressures. Otherwise, my Prius rides like the Flintstones car! Like a rock! Why do you need such high psi in a Prime? Is 196 mpg not good enuf? :ROFLMAO: I like a smoooooooth ride. ;)

    Like traveling through space.... silent and smooth. :cool:
     
    #26 Starship16, Jun 17, 2018
    Last edited: Jun 17, 2018
  7. Andyprius1

    Andyprius1 Senior Member

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    It’s not for mpg, an example: I have a rental car right now and no doubt they set the pressure at recommended. Freeway pavement was very hot and I got a tpms warning, all 4 tires were around 30. I couldn’t tell by just looking so I filled them up to 50, no more problems. It just gives one leeway that’s all.
    50 lbs is not high. IMO
     
  8. krmcg

    krmcg Lowered Blizzard Pearl Beauty

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    And better tire wear.
     
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  9. Starship16

    Starship16 Senior Member

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    I have the Michelin premier tires. The sidewall says do not exceed 44 psi. I'm a go by the book man! ( blame it on that good Air Force training.) I would never exceed 44, or come anywhere near that level.

    I stick to the factory recommended pressure of 36 front and 35 rear. My Prius rides and handles just fine at that level. That's good enough for me.

    I did bump it up to 42 psi for a time, and that car felt like I was riding in a stage coach over broken asphalt. :D
     
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  10. Andyprius1

    Andyprius1 Senior Member

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    That’s the pressure at which the tire seats onto the rim, the mechanic often has to exceed this pressure.
     
  11. Starship16

    Starship16 Senior Member

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    Maybe so, but he only exceeds it very briefly. And he doesn't have to drive that car that's riding on rocks!

    With all due respect gentlemen, we will just have to agree to disagree. I like a smooth riding car. And hopefully, as quiet as possible. The roads in my area are full of potholes. When I hit one of those with high tire pressure, it rattled my teeth!
    (And knocked the chili-cheese dog right out of my hand! :confused::ROFLMAO::eek:)
     
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  12. momto4girls

    momto4girls Junior Member

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    Yes, I'm starting to think its just an oddity, too. I MUST read my manual, so that I can understand what all the different displays are telling me. I just made a trip to Target. Before I left I pushed the trip button until the little car with the flag showed up. On the trip home I drove 12.1 miles and got 59.1 mpg. This was mostly interstate in a torrential downpour, so my speeds were between 30-50 mph. Lots of water on the road. Anyway, 59 is about what I would expect. I normally have the odometer set to my total miles (26000). That's the number that dropped. I think everything is fine. I appreciate everyone's help. Any other tips are appreciated.
     
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  13. Mendel Leisk

    Mendel Leisk EGR Fanatic

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    Sounds good, I was on the edge of grump I guess.

    Just checked, it's 84 F here, probably tick up a bit more.

    IMG_8844.jpg
     
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  14. Andyprius1

    Andyprius1 Senior Member

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    You have the right to set the pressure anywhere you like
     
  15. Starship16

    Starship16 Senior Member

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    Tips? Yes, try to ignore all those screens and displays and just drive it. :)

    All that stuff on those screens just distracts me. It was fun at first, watching all those dancing lines and graphs and displays, and then it all got old and boring. Now I just drive the car like a normal car, and enjoy it.:D

    And yes, driving through rain will definitely affect the mpg numbers on the computer. I'm not sure I even believe it! Sometimes this Prius can be very picky and weird. I think it's way too over complicated, but that just gets me in trouble when I mention it. Have fun.;)



    Not a right, it's just a choice that I prefer. I don't like riding on rockhard tires. And I don't like my teeth falling out! :eek::ROFLMAO:
     
    #35 Starship16, Jun 17, 2018
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  16. Andyprius1

    Andyprius1 Senior Member

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    To remind posters, this is a Prime Post.
     
  17. Starship16

    Starship16 Senior Member

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    meaning what? Mom, the original poster has a 2016 Two model
     
  18. Andyprius1

    Andyprius1 Senior Member

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    Meaning the Prime and the 2016 are different and we don’t allow aliens from Pluto to post.
     
  19. Andyprius1

    Andyprius1 Senior Member

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    I do like your Avatar tho
     
  20. Starship16

    Starship16 Senior Member

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    Well, tires are tires. And mom was asking about a drop in gas mileage. We all hijacked her thread. Sorry, mom.

    (And I just made my way to Mercury. What a tiny place! :LOL:)
     
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