Front Cylinder Running Rich Rear Cylinder Running Lean

Discussion in 'Other Service and Maintenance' started by 04 Road King, Jan 19, 2015.

  1. 04 Road King

    04 Road King New Member

    3
    0
    0
    I have a problem with my 04' Road King Custom EFI. The front cylinder is running real rich and the rear cylinder is running real lean. I have S&S head. I did a leak down test and both cylinders are at about 2%. I pulled the injector and cleaned them by back flushing. I swapped the spark plug wires and the plugs. After all this being done the cylinders are rich and lean with no change. If I rev the engine to 3000 rpm the AFR in both cylinders gets in range. Any help would be appreciated. Oh I have Daytona Twin Tech TCFI.
     
  2. Jeff Klarich

    Jeff Klarich Well-Known Member Contributor

    3,602
    103
    296
    Are you fouling the front plug? Why do you believe the the front is to rich and the rear is to lean? How long have you had this experience? Have you made any mods or done any work lately? My experience has been the front plug does run a little richer than the rear.
     
  3. 04 Road King

    04 Road King New Member

    3
    0
    0
    I foul the front plug if I let it idle for a period of time. If I take the bike out and run it hard for 20 or 30 miles it seems to clean the plug up a little bit. The rear plug is still like chalk. I bought this 04 Road King with these upgrades. I got a good deal on the bike, that's the reason I bought the bike. The guy I bought the bike from didn't have much information about the motor. I have been searching serial #'s down trying to find out what kind of upgrades have been done to the engine. I have been experiencing this sense I bought it in March of 2014. was told that the engine has less than 5000 miles on the motor. The pistons and the heads look brand new like it's burning clean. The front plug is black and the rear plug is white. I have done a leak down test and got about 4 to 5% on the front and the rear cylinders. I have checked for intake leaks. I have also pulled both injectors and cleaned them with carb cleaner using a 9 volt battery. I have swapped the injectors and the O2 sensors to see if the problem followed the parts. I have tried to manually tune the Daytona twin tech TCFI and the the AFR on the front returns back to running rich and the rear to lean according to the live data log. I am not very savy with the Daytona Twin tech system. This is my first custom bike also with EFI. I had a Fat boy with carbs and it was no problem to tune.

    Thanks,
    Teddy Stevens

    Sorry for the long reply. I hope that I give enough info.
     
    Last edited by a moderator: Jan 22, 2015
  4. stray dog

    stray dog Junior Member

    443
    26
    0
    Do you have a good and even spark between both cyl's?

    I would call Daytona Twin Tech and talk with them. Check to see which Fuel Ignition Controller you have first. Hopefully they have some insight.
     
  5. Jack Klarich

    Jack Klarich Expert Member

    18,544
    153
    399
    Can you disconnect the Twin Tech and see how it runs?
     
  6. stray dog

    stray dog Junior Member

    443
    26
    0
    Jack,
    That's what I was thinking also. I don't know anything about this, but just skimming the website, it appears this is a programmable replacement for the stock ignition module..?? In which case it is not just a piggy back tuner.
     
  7. Jeff Klarich

    Jeff Klarich Well-Known Member Contributor

    3,602
    103
    296
    +1 on the above posts, seems like your dumping to much fuel in the front and not enough in the rear cylinder. A white or chalky color rear plug is way to lean as you indicated.
     
  8. 04 Road King

    04 Road King New Member

    3
    0
    0
    The Daytona Twin Tech replaces the factory ECM. I do not have the factory ECM to eliminate daytona twin tech

    I have manually tuned the front and the rear AFR and the bike runs great for 2 or 3 min and them you can tell that the AFR changes back to rich in the front and lean in the rear. I am at wits end. I am not sure what else to do but to take to a mech $$$$$$$$$$$$$. Any ideas.
     
    Last edited by a moderator: Jan 23, 2015
  9. Bodeen

    Bodeen Well-Known Member Staff Member Moderator Contributor

    4,317
    73
    130
    I would call DTT. Tech support and ask them.

    (386) 304-0700
     
  10. stray dog

    stray dog Junior Member

    443
    26
    0
    The history on this bike and motor build is a mystery and is intriguing. Someone put some nice S&S heads on, have to wonder what the rest of the build is. What is the ccp? You may be sitting on a nice build that someone just gave up on.

    Maybe DDT wrote a custom map and with vin #'s could tell you what's in the motor. Probably grasping at straws there.

    In any case it seems as tho you found the problem when you said in post #3 "I have tried to manually tune the Daytona twin tech TCFI and the the AFR on the front returns back to running rich and the rear to lean according to the live data log".....the ecm is not storing/saving your tune.

    Please keep us up to date on this 04rk and good luck!