New 2012 Accent 5 Door Hatch Eltrolyte Green

Discussion in 'Hyundai' started by joesgot4, Jul 22, 2011.

  1. MaxxMPG

    MaxxMPG Hasta Lavista AAA-Vee Von't Be Bach

    A couple of thoughts on the aFCD inaccuracy...
    1 - It is a running average of fuel used and distance travelled since last reset of the gage. I find that they are accurate if you drive "only city" or "only highway", but they start to stray when mix some optimal 50mph highway travel with an hour of city slogging. Add in either of the two extremes and the gage will be off by more than a couple of mpg.

    2 - The tank in the Accent is small, and when you're over 50mpg, half a gallon of gas is good for 25 miles. Adding fuel at another gas station whose pump kicks off a half a gallon early or late will result is a slight overfill/underfill that is much more dramatic when you're talking about lots of miles and relatively few gallons.

    3 - At 58mpg, being off 5mpg is the same inaccuracy as a gage that reads 29mpg and is off by 2.5mpg, or a gage that reads 14.5mpg instead of 13.3.

    In short, you never want to trust the aFCD as your actual gas mileage. The correct figure is miles driven divided by gallons added. The aFCD is useful as a running scorecard for how you're doing, but it won't usually match up with true mpg. In my Elantra, I find that the aFCD is about 4% over, but the odometer is almost 4% under, which means that it's fairly accurate if I adjust for the odometer offset.
  2. joesgot4

    joesgot4 Well-Known Member

    just checked the mpg's on a 90% highway and 10% city trip my fcd read 52.6 and my actual gas added gave me 52.5mpg and thats at 55mph! so at
    i'll do another run thursday at 45mph! p.s. everyone at work laughs at me for my speed!
  3. Right Lane Cruiser

    Right Lane Cruiser Penguin of Notagascar

    Yeah, my coworkers laugh too... but I average about 1/5 of their fuel usage for the same distance. ;)
  4. ItsNotAboutTheMoney

    ItsNotAboutTheMoney Super Moderator Staff Member

    Just tell them you drive at 52.5mpg. :D

    You should be trying between 50 and 55 too: find the sweet spot where mpg equals mph. Then ask them where their sweet spot is.
  5. RedylC94

    RedylC94 Well-Known Member

    Actually, that would be finding the speed you can maintain with a fuel flow rate of one gallon per hour. (Imagine how rapidly cars would improve in efficiency if limited by law to 1 gph!)
  6. joesgot4

    joesgot4 Well-Known Member

    i was doing a fuel mileage run thursday evening and suffering with 100 degree temps and not running AC ! the fcd was at 66mpgs at 45mph steady state just monitoring rpms! i was 125 miles into my run and thinking of all my personal records i was about to smash and came into a violent thunderstorm with winds 40--55mph! i really got scared cause a couple times i could hardly stay on the roadway! the rain was such that i had to run defrost to see! and the wipers on full on! so instead of smashing my records i quit driving for fuel economy and started driving just to get home! i ran the defrost and ac for the last 60 miles and i stayed in those bad winds all the way home ! i also drove 60mph when i could and i finished with my display reading 52mpg and i did not do a fill up check! i'll do another fuel mileage run early monday morning!
  7. joesgot4

    joesgot4 Well-Known Member

    i'll have some concrete numbers by tomorrow morning, but the display shows 57.3mpg driving 45mph steady state on mostly flat highway with some rolling hills! i'll predict at least 55-56mpg! i engine on coasted some! and drove without braking most of the time ! cruise control on 75% of time and it only shifted down 2 times over the whole 175 mile trip! i'll let yall know tomorrow morning!
  8. joesgot4

    joesgot4 Well-Known Member

    alright every week this number seems to go up,and up, and up! actual mileage on my last 177 mile trip from fill up to fill up was 56.79mpg's! so yall know what number i have fixed in my sites is 60 mpg! i will have to go "advanced" to get that number but i'm pretty sure its there for the taking! i wish WAYNE could drive my car to see what its capable of!
  9. Right Lane Cruiser

    Right Lane Cruiser Penguin of Notagascar

    Time to change your vehicle list and signature banner. :D:thumbs_up:
  10. FSUspectra

    FSUspectra Practicing true conservatism!

    Agreed, whatcha waiting for? ;)
  11. ItsNotAboutTheMoney

    ItsNotAboutTheMoney Super Moderator Staff Member

    Mileage log or it didn't happen. :D
  12. joesgot4

    joesgot4 Well-Known Member

    i have a mileage log with 4 entries
  13. ItsNotAboutTheMoney

    ItsNotAboutTheMoney Super Moderator Staff Member

    OK, mileage log linked from an image in your signature or it didn't happen. :D
  14. dqniel

    dqniel New Member

    Thanks for giving all this info. I'm about to buy a new car, and my decision is down to the Accent and Mazda2. I prefer the handling of the 2, but prefer the cargo space and lower RPMs at highway of the Accent. Decisions, decisions.
  15. schuylkill

    schuylkill Well-Known Member

    I don't nearly understand all of the issues but I would research the direct injected engines used on some of the newer high mpg cars before making a decision, I know the Accent is one. There is discussion on this over at BITOG.

Share This Page