Bad Fuel Mileage

Discussion in 'Engine, Fuel and Exhaust' started by MarkS, Feb 10, 2015.

  1. MarkS

    MarkS Member

    93
    0
    0
    I have a 2013 Harley Iron (efi) that has 6500 miles on it. I put on AN big suckered and VA short shots @ 1000 miles. It's getting 31.9 mug with fuel programmer off and should be around 48 mpg. I've run it with no issues for 2 years and now fuel mileage went down bad. Any ideas?
     
  2. dbmg

    dbmg Experienced Member

    5,800
    153
    318
    I do not understand are you or are you not using some type of fueler? For mileage to drop all of a sudden on a EFI bike the check engine light should be on and it should be performing poorly. Maybe fueler bad?
     
  3. MarkS

    MarkS Member

    93
    0
    0
    I had a EJK gen 3 that's being checked now and bikes back to stock but still getting 32 mpg. It should be in high 40's.

    I was thinking bad fueled myself but now I'm thinking maybe my bike. I'm confused!

    BTW no check engine light on and bikes running good. I'm not running it harder than normal. With fueler on I've always gotten 38 in town and 42 on highway with extra fuel added.

    With fueler off it should be running really lean and getting higher fuel mileage right? Like stock mileage?
     
    Last edited by a moderator: Feb 11, 2015
  4. dbmg

    dbmg Experienced Member

    5,800
    153
    318
    You would think. But with a excessive lean mixture due to high flow air filter and the exhaust you have installed with minimal or no back pressure back pressure, with out fueler to enrichen system mileage will fall flat for you need to crank throttle more to make bike run. I am surprised that you do not have a check engine light and serious flat spot in throttle while riding with out fueler which is ill advised with bike being so lean.:(

    Here is a good read and current tread:

    Dobeck or no Dobeck? - Harley Davidson Forums - HDTalking.com
     
  5. stray dog

    stray dog Junior Member

    443
    26
    0
    Did you remove the baffles from the VA short shots ?
     
  6. dolt

    dolt Senior Member Contributor

    1,813
    83
    201
    A drop in fuel mileage from 48 to 31 would have to exhibit a noticeable drop in performance somewhere in the rpm range but you say the bike is "running good"; doesn't add up. However, a drop from 42 to 38 could be due to a heavier right hand, terrain, wind, heavier load, etc. and nothing to be concerned about. I see that kind of change in mileage on a windy day.

    When you disconnected the Dobeck unit, did you re-install the OEM O2 sensors? Obvious right, but had to ask.

    Have you made any other changes to the bike recently?
     
  7. MarkS

    MarkS Member

    93
    0
    0
    No I didn't.

    Did not hook up 02 sensors!:(:(

    Took it to harley to day and they ran check on bike and said they couldn't find any engine failure other than it needs tunning. Maybe just bad fueler?? We'll see what Do beck says on my fueler.

    Would not plugging the 02 sensors back in kill stock mileage?
     
    Last edited by a moderator: Feb 11, 2015
  8. Jack Klarich

    Jack Klarich Expert Member

    18,544
    153
    399
    Nah, the Ecm would be looking for a decent AFR
     
  9. MarkS

    MarkS Member

    93
    0
    0
    They of course suggest the super tuner and DYNO to fix the problem. Just $772.42 out the door!:mad:
     
  10. Jeff Klarich

    Jeff Klarich Well-Known Member Contributor

    3,593
    103
    296
    JMO if you removed the fueler you'll want to hook up the 02 sensor again. If not you'll probably throw a code.