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Should I be worried ?

Discussion in 'Prius c Fuel Economy' started by Gerry miles, Sep 13, 2015.

  1. Gerry miles

    Gerry miles New Member

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    After my three months of my driving my new priusc2, I got my first oil change,at 10,600 kms, yes that being said, the day after I encountered my very first problem with my car, while driving your current fuel consumption rating the always changes while you drive at varying speeds all of a sudden stuck on 4.7/100, no matter how slow I drove or how fast I went the rating never changed. Until I pulled over and stopped.turned off the car. Then restarted it and began driving again say around 60 kph, the rating then would change like 3.8/100 or if I drove faster so would the rating change accordingly. Now yesterday two weeks after that incident, it has done it again, while driving it, got stuck on 4.7/100 and I knew something was wrong because I went from 100 to 80 kph, and nothing changed and drove for awhile at 50 kph, until I pulled over turned off car and restarted, once I regain a normal speed,it recalculated my current fuel consumption rating of say 3.2/100 while is was lightly going 70 kph. So how would the dealership check this plm out ? Its pissing me off with a new car just three or four months old and the computer is having this glitch.
     
  2. jadziasman

    jadziasman Prius owner emeritus

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    Explain this to the dealership you take your car to. It's still covered by warranty. Sure it's a hassle
    but you do want it fixed don't you?

    Who did the oil change? Is it related to your issue? Maybe.

    You should change your profile information. Your vehicle is a 2015 not a 2012, right?
     
  3. bisco

    bisco cookie crumbler

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    worrying won't fix it, action will.
     
  4. The Electric Me

    The Electric Me Go Speed Go!

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    We all want our new vehicle to be the one without the glitch or the problem.
    And as hard as manufacturers try, it's still impossible to build all of them absolutely perfectly, all the time. Glitch Happens!.

    Better that you discover it now, while still under warranty, than have this problem manifest 3 or more years from now.

    As far as how would the dealership check this problem out?

    I don't know if they would have a diagnostic that would directly test that gauge or reading....maybe.
    But at the very least, if it's happening to you with common regularity, hopefully you could take it in, and have a tech ride along and reproduce the symptoms.

    Disappointing when owning a new vehicle yes, but your best move at this point is to start the process of documentation of the problem and attempted repair and remedy.

    Curious that it should manifest right after an oil change, and I'm far from an expert, but I can't imagine what with an Oil Change could possible affect that system. If they DO find a connection let us know, I'd like to know what it is.
     
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  5. Gerry miles

    Gerry miles New Member

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    Yeah yesterday it happened again but more frequently, and even after I stopped and turn the car off and restarted it still would not show anything below 4.7/100 as I drove varying speeds. Then towards the end of my drive, I stopped at a car wash gave the car a good wash from all the road dust. And final drive home from nearly 50.5 kms I used up only $1.80 of gas and I was getting a good reading of 3.7/100 which was more in line with my constant speed of 80-90 kph and slower in the city. Later that night getting pizza I was averaging 3.1/100 driving in the city. So I know when its working right and when it gets stuck at the stupid reading of 4.7/100 is very annoying, but I will be dropping by my local dealership and explaining my plm to them, and I will update anything they do to resolve this issue.
     
  6. Gerry miles

    Gerry miles New Member

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    Well here is the outcome, got ahold of my dealer, they passed me to the general manager, he takes my issue to Toyota Canada, and after many pictures of examples I send him of good readings to bad readings on the very same commute.he books me in to have the car scanned, and give me a courtesy car. I drive to the shop less than 5 km away. I know its acting up because I'm getting 5.0/100 on the drive. The tech guy agrees to come out side and explain that I don't really understand what I'm talking about but will take the car out for a test drive, we drive a bit outside the city conservative speed. And stops it reads 4.9/100. Then he drives back to the garage this time faster more heavier on the pedal. We get back and its reading 4.9/100. There was his point that to him there was nothing wrong on the car. So I shake his hand apologize for being silly new hybrid driver. And I drive home the very same way I came , I get home and my car is now reading 2.7/100 and says I used only .12 cents of gas to drive 5 km. Yep I really don't know what I'm talking about.
     
  7. bisco

    bisco cookie crumbler

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    i'm not sure i know what you're talking about.:p
     
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  8. priustexasbob

    priustexasbob Member

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    is this true with any of the display modes? have you tried to go into the set up, turn off a mode then restart the mode and see if that effects it?
     
  9. Gerry miles

    Gerry miles New Member

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    What is there to reset , I'm talking about the display right beside the odometer, the fuel consumption ratio that changes every ten seconds as you drive, sure you could look at the mid dash display and watch a bar graph go up and down in real time but does not give you exact numbers just a graph, when I'm driving its alot easier to look at your dash mount ,no matter what display you change up there it will always show your current gas consumption /100. I know this is really hard for Prius owners to understand because their system works, but when I commute the same road back and forth I expect just a little variance to change like windy, cool, traffic tie ups, but dam when I get on average 3.8-3.5 /100 getting to work now all of a sudden I'm getting 6.2-5.5/100 and yet the cost used getting there has not changed.something is wrong. Yes I know when your driving it takes a little while for the initial start up 15/100 to work down. But come on dam it, leaving the Toyota lot driving home discouraged that the shop tech has no idea of what your talking about and he is spouting off fractions of consumption by 1000 km and this divided by that, you not going to see a big difference, OK you snowed me about technical gobble gook, to make yourself sound important. Then I drive home it was actually my third best score of 2.6/100 using 12 cents worth of gas based on my last fill up,and I religiously change the price of litres when I fill up. He is telling me that on this colder temperatures I will not see much of the 3/100 and there I just proved a third best score of fuel savings. Four months of owning my car driving over 14,500 km do you not think I know when something is not giving a proper reading , when my driving is only improving. I hate it when people act like you know nothing and I'm getting upset over nothing. I bought my dream car and its not giving accurate reading s 100 % of the time.do you buy a hybrid car and drive without any sensers working, do people not try to drive their car and get the best gas mileage they can, or do people just drive their car because it has a Prius c badge on it. ?
     
    #9 Gerry miles, Oct 1, 2015
    Last edited by a moderator: Oct 23, 2015
  10. priustexasbob

    priustexasbob Member

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    I did not mean to upset you. sorry
     
  11. Sean Nelson

    Sean Nelson Active Member

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    I very strongly suspect that what is happening is that you're simply seeing the results of having driven a longer distance. If I drive for one km at an average fuel consumption of 4.0 litres per 100km and then I drive the next one 1km at an average fuel consumption of 5.0l/100km, then at the end of the second kilometer the display will show 4.5l/100km.

    But if I drive 100km at 4.0l/100km and then drive the next one km at 5.0l/100km, the display is still going to show 4.0l/100km because that last one km is such a small part of the overall distance. In other words, the fuel economy display doesn't show you the current fuel economy, it shows you the average since you started the car (or, if you're looking at the "Trip 1" or "Trip 2" display, since you reset the trip odometer). So the longer you drive, the less you'll see the fuel economy change because any immediate differences in driving conditions are so small compared to the length of the drive you've already completed.

    If you want to see your "current" fuel economy then switch to the screen that shows the bar graphs of fuel economy at 5-minute intervals (last 5, 10, 15, 20, 25 and 30 minutes). The rightmost bar shows you the economy you're getting "right now" without any averaging.
     
  12. InPriusLove

    InPriusLove Member

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    Driving an American Prius C nothing is in km. But I know we have a choice of screens. Can you please explain which screen you are using? The Eco score, for example, the three bars measuring such and so out of 100, is something that I am intrigued by but fail to understand. It has no obvious bearing on mileage but does give a rating of the most economical use of the hybrid system versus the least economical use of it. Mine has whole numbers, like 40, 50, 85 and so on, as a ratio against 100. This is the most familiar thing. You are describing something that is next to the odometer. The odometer shows on numerous screens. Then there is the concept of whether or not it is feasible for you to go a distance for a paltry expense, yes it is. But the average referred to above seems the best answer. It is the 100 factor that confuses me in what you are saying.

    For a realistic understanding get to know your choice of screens.
     
  13. RRxing

    RRxing Senior Member

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    No, the technical explanation is the one that I'd be more inclined to understand/believe, instead of one that dumbs it down to be almost meaningless.
     
  14. SwhitePC

    SwhitePC Active Member

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    us americans are so confused...we use liters to describe the size of the engine, then we go about using miles and gallons for everything else about the vehicle, lol...we just don't know what system of measurement to use or stick to
     
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  15. Sean Nelson

    Sean Nelson Active Member

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    I'm using the fuel economy reported at the very top of the screen - the part that doesn't change when you flip from one display to the next. Mine is a Canadian Prius so it reports fuel economy in litres used per 100km of travel which, as I understand it, is the standard way to do this everywhere other than America. In America this section of the screen shows "MPG" (miles per gallon).

    I used litres/100km because that's what the Original Poster used, so my answer was intended to be understood by him. He was concerned because after driving around for a while he said his fuel economy figure got "stuck" on a number and wouldn't move. But I can state my response in MPG terms as well: If you drive for 100 miles and your display reads 50MPG, you shouldn't expect the MPG figure to change significantly over the next mile even if you drive that mile up a hill getting only 40MPG. The overall effect on fuel economy you get during that last mile is small compared to the economy you've been getting over the previous 100 miles. That's because the figure being displayed in that top part of the screen is an average since the car was started (or since you last reset the trip odometer, depending on which odometer you're looking at) and not a "current" figure. Because of that, the further you drive the less impact your current driving conditions will have on the average fuel economy being shown, until you reset it (either by stopping/starting the car or by resetting that trip odometer).

    Nothing that I've discussed in this thread has anything to do with the "Eco Score". The standard way to measure fuel economy in Metric countries is to use litres per 100 kilometers - the "100 kilometers" is an arbitrary distance and has nothing to do with the maximum Eco Score. And my examples of driving 100km at one fuel economy and the next km at a different one (or 100miles and then 1 more mile) are again using an arbitrary distance and have nothing to do with the Eco Score.
     
  16. Mendel Leisk

    Mendel Leisk EGR Fanatic

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    Metric fuel consumption could be in km's per liter. But you know metric, gotta be different. :)

    Liters per 100 kilometers is kinda like being on Jeopardy, everything backwards. After a while you get used to it, lol.
     
  17. dborn

    dborn Junior Member

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    It's only logical if you're referring to fuel consumption, to express it in amount of fuel used per fixed distance.

    Miles per gallon is a measure of how far you can go on a set amount of fuel. It is more a measure of fuel autonomy than fuel consumption. Makes sense? :)
     
  18. Sean Nelson

    Sean Nelson Active Member

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    Dborn is right - volume of fuel per some given distance gives you a number that reflects actual fuel consumption and as such is, IMHO, a more direct measure of fuel economy. A l/100km figure is more economical if it's lower, same as the price of some good or service. MPG is more of a "range" measurement - if you know how many gallons you've got it makes it easy to figure out how far you'll get before you run out of fuel.

    But you're right - it's whatever you've grown accustomed to using.
     
  19. Mendel Leisk

    Mendel Leisk EGR Fanatic

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    Maybe that's why Americans like to push tanks, lol.
     
  20. CR94

    CR94 Senior Member

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    Much ado about nothing ...
    It doesn't really matter. Quantity "X" provides exactly the same information as "1/X" , as long as you can comprehend the difference between multiplication and division.