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Are Hyundai MPG displays accurate?

Discussion in 'Hyundai/Kia/Genesis Hybrids and EVs' started by Leadfoot J. McCoalroller, Nov 4, 2018.

  1. Leadfoot J. McCoalroller

    Leadfoot J. McCoalroller Senior Member

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    I just turned in my rental for the week, a 2018 Elantra. The last trip was ~40 miles on mostly empty freeways. Temperate weather in L.A., though I did have the A/C on. Lots of cruise control use, 63-70 MPH most of the time.

    The dashboard display claimed I was getting 59.5 MPG until I started climbing the Sepulveda pass on the 405. Even after that and crawling around LAX, it showed 53.x.

    I thought that was pretty impressive for a plain gasser, unless it's lying. I know Hyundai got in trouble for overstating economy a few years ago, but... ?
     
  2. dubit

    dubit Senior Member

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    I took a look at Fuelly - Track and Compare your MPG and it's showing the users there getting right about 30 mpg.

    {edit} - hmm that link wasn't there when I hit reply. But it's fuelly.com
     
  3. Trollbait

    Trollbait It's a D&D thing

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    Most of those displays are optimistic, and then they can be measuring different data sets. I've had trips in the Camry that were over 40mpg, and can keep the instant MPG in the 50's for stretches. A reset, whether by user or a quit stop with engine off, of the display while everything is warmed up can report better than typical numbers.
     
  4. Leadfoot J. McCoalroller

    Leadfoot J. McCoalroller Senior Member

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    Hmm. I did top off the fuel in that car just before that trip, that's the only possible reset I can think of. I didn't manipulate any detail controls at all- it was a rental after all. The display was clearly labeled "average" and there was a more believable instant meter elsewhere on the screen. Conditions were ideal for getting good MPG but... somehow I doubt it was really that good.
     
  5. Trollbait

    Trollbait It's a D&D thing

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    The Camry can display instant, trip, tank, and lifetime until reset fuel economy. The trip resets when the car is shut down, and the tank on a fill up. The Elantra was likely warmed up during the trip to the station, so seeing high numbers doing ideal highway cruising on a reset gauge wouldn't be out of line. Figure the gauge is 5% to 10% optimistic(the Camry's is 6%).
     
  6. Leadfoot J. McCoalroller

    Leadfoot J. McCoalroller Senior Member

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    This week's rental is a 2018 Chevy Malibu and it's telling me I scored 40.1 MPG on a 160-mile trip. That is somewhat more believable, though it sure is a heavy car.
     
  7. Tideland Prius

    Tideland Prius Moderator of the North
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    The 40mpg on the Malibu is much more believable than the 59mpg on the Elantra (at those speeds). I am able to hit 55mpg on the current gen Corolla (but it has a CVT compared to a regular automatic or dual-clutch depending on the Elantra model) but those were at 50mph, not 63-70mph.
     
  8. Trollbait

    Trollbait It's a D&D thing

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    My 2016 Camry has a 35mpg highway rating. Cruising at those speeds, the reported tank average can be over 38mpg. The instant MPG bar tops out at 60mpg.

    The 2019 Elantra is 40mpg highway. Without a cold start penalty, the reported value can be that high from an optimistic gauge. Want to know what it actually got, you have to calculate a tank, or calibrate a scanguage for the specific car.
     
  9. ZA_Andy

    ZA_Andy Member

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    Just one real-world example of the difference between displayed MPG and actual: Hyundai Ioniq SEL Hybrid display at 61.8, and calculated from fill-up 60.3.
     
  10. Salamander_King

    Salamander_King Senior Member

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    That's more accurate than most Prius mpg display I have seen. Prius (both Gen3 and PRIME) display is almost always 5-8% more optimistic than calculated by full-tank method.
     
  11. ZA_Andy

    ZA_Andy Member

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    My Gen 3 Prius was typically about 5% optimistic, but the Gen 2 I had was closer, more like 2%. Both were pretty consistent however, so while the numbers weren't exactly right, consumption trends by driving habits and routes were.
     
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  12. Salamander_King

    Salamander_King Senior Member

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    I know this is an old thread. But are modern gassers really that fuel efficient? My last gasser I drove was our old 2005 Sienna AWD which I got rid of last year. I was never able to get anything better than 24 mpg on hwy, typically less than 20 mpg in town. Of course it was V6, AWD and a minivan. For an economy 4 cylinder compact gasser, I have to go back to '98 Civic sedan. I was not that fuel efficiency conscience back then, and didn't keep any record, but I don't think it got much better than ~30 mpg? Even my first hybrid 08 HCH got lifetime 43.1 mpg. We currently have three cars all hybrid in our household, but if new gasser can get 40-50 mpg, then I must be doing something wrong with my selection of cars.:(
     
    #12 Salamander_King, Apr 25, 2019
    Last edited: Apr 25, 2019
  13. Leadfoot J. McCoalroller

    Leadfoot J. McCoalroller Senior Member

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    Some are. I rent a lot of cars for work, so I get to try a lot of new-ish cars. That one Hyundai really stood out with its built-in computer claiming 59, but quite a few cars are turning in an honest 40+ nowadays. I think that's a lot of why hybrid sales have dropped- you can save almost as much gas with a newer ordinary car and no expensive battery replacement bogeyman depressing your resale value.
     
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  14. Salamander_King

    Salamander_King Senior Member

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    I had to look it up myself. Here is the list of BEST 10 most fuel efficient 2019 non-hybrid, non-EV gasser by EPA rating. source: 10 Most Fuel-Efficient Non-Hybrid/Electric Cars For 2019

    1. Mitsubishi Mirage 36 City / 43 Highway / 39 Combined
    2. Chevrolet Cruze Diesel Sedan 31 City / 48 Highway / 37 Combined
    3. Toyota Corolla Hatchback (Tie) 32 City / 42 Highway / 36 Combined
    3. Honda Civic Sedan 1.5T (Tie) 32 City / 42 Highway / 36 Combined
    3. Jaguar XE Diesel (Tie) 32 City / 42 Highway / 36 Combined
    6. Honda Fit 33 City / 40 Highway / 36 Combined
    7. Toyota Yaris Sedan (Tie) 32 City / 40 Highway / 35 Combined
    7. Hyundai Elantra Eco (Tie) 32 City / 40 Highway / 35 Combined
    9. Jaguar XF Diesel 31 City / 42 Highway / 35 Combined
    10. Kia Forte FE 31 City / 41 Highway / 35 Combined

    None are rated >40mpg for combined. The best in city mpg is 36 mpg. Most are either subcompact or compact car or if larger it is diesel. If those EPA numbers are accurate, PRIUS or even my old 2008 HCH is still better fuel efficiency wise. But in real world, if they are able to score >40 mpg in mostly city drive, then I really have to re-think my next car purchase choices.
     
    #14 Salamander_King, Apr 25, 2019
    Last edited: Apr 25, 2019
  15. mpg_numbers_guy

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    It all depends on the driver. On the '04 Sienna (FWD, not AWD) that my family had, I was able to get ~28 MPG city and ~32 MPG highway when I drove it conservatively. My family regularly got 24 MPG city, 29 MPG highway driving it normally. Compared to our old '06 Chrysler minivan that got 22 MPG combined and the '01 Pontiac minivan that got 24 MPG combined.

    Hybrids don't really get better fuel economy on the highway; around town they excel because the braking and acceleration can be taken upon by the battery. Driving conscientiously can also reduce the fuel economy hit around town.

    Check out Fuelly for accurate, real world numbers.
     
  16. ZA_Andy

    ZA_Andy Member

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    I don't know that EPA figures are reliable, but they should be fairly consistent for comparative purposes. As such, I'd think that a Prius wouldn't really be worth the premium if the majority of driving is highway, where mine, for example, rarely much bettered 50mpg once it was above 65mph. It did return a fairly reliable 55mpg at 55mph however.

    Where the Prius really shone was city, where 'gassers' rarely return much better than 30mpg, but the Prius could get around 60.
     
  17. Trollbait

    Trollbait It's a D&D thing

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    The lifetime for my 2016 Camry is 34mpg(display is about 2mpg higher) on a commute that I'd say is two thirds highway. I haven't installed the scangauge yet. The Sonic was around 37mpg lifetime with the scangauge. Most drivers would get lower since I expect they wouldn't keep the turbo out of boost.

    Engine efficiency has simply gotten better over time. The majority of the improvements seen in the Prius is because of the engine.
    It is also why the small(Rav4 class) SUVs have become popular. They are as efficient, maybe better, than the older car they are replacing.
     
  18. Salamander_King

    Salamander_King Senior Member

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    Was you Sienna V6? Though I am not sure if Sienna was ever fitted with 4 cylinder engine. The AWD Sienna was our last minivan. We did own Dodge Grand Caravan, and Nissan Quest twice before that. But I was not even thinking of fuel efficiency those days. Not sure how they did compared to AWD V6 Sienna we had. We recently purchased used Pathfinder Hybrid to replace our minivan needs. It gets better mileage than our old Sienna, but still not good enough to my liking. :cry:

    I think EPA figures got much better in last ten years, and more comparable to the real life mpg. That said YMMV is always true. And yes, Prius for city drive is always the best. My current drive is 80%+ in city and very little highway drive. If any gasser that can do >40 mpg in city, I may have to pick it for my next commuter.
     
    #18 Salamander_King, Apr 25, 2019
    Last edited: Apr 25, 2019
  19. Tideland Prius

    Tideland Prius Moderator of the North
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    It depends. For city driving/urban driving, a Prius or any full hybrid still wins. For highway driving (actual high speed), hybrids still win but the margin is small (~5-10mpg) compared to the 20mpg margin for city.

    For lower speed highway driving, it’s very possible to hit 45-50mpg on the latest compact cars with CVTs and the latest engine technology. I can see 50mpg on a 2014 Corolla at 50mph. That dropped to 43mpg at 62mph and to 39mph at 65-70mph. It was repeated with another 2017 Corolla rental (that had winter tires on).

    But put them in the city and I see 23-32mpg depending on terrain and traffic.

    A hybrid allows you a owner to consistently see high mpg in a wider range of conditions.
     
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  20. Salamander_King

    Salamander_King Senior Member

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    Thanks for the explanation. I am relieved to know that I am still driving the most fuel efficient car for my use. If my life style changes in someway that requires more frequent highway drives, then a gasser may gets on my next car buying list.;)