bad ecm ?

Discussion in 'Electrical' started by whitebuell, Aug 30, 2014.

  1. whitebuell

    whitebuell Member

    I have a strange problem with a 06 roadking , engine runs very rough...only the rear cylinder seems te fire.The front one seems only to fire very poor every 2 revolutions of the engine.
    DTC code :p0262 front injector faulty
    Changed the injectors because the bike still had the 8° injectors and put some 25° injectors instead,bike fires right up but keeps running on 1 cylinder.
    Still the same DTC code present !
    Did al the resistance tests with a break out box and the other stuff by the(electric diagnostic manual) book, everything ok ....the only thing that's left is a bad ECM but that's 5OO+ euro's ,a lot of money to try out .
    When I let the injectors hang out of the inlet and start the engine, they spray like they should , at least , that what it looks like.
    Tested the ignition coil and wires, all ok , even changed the coil and wires/spark plugs, all stays the same.
    bike is stock with only open exhausts and a Direct Link tuning map in the ECM.
    has somebody ever encounterd this problem ?
    Thx for thinking with me !
  2. bcortani

    bcortani Active Member

    I have an 08 Softail (11000 miles) with a somewhat similar problem. Mine acts the same, but only after hot (15-20 minutes of running around) then will stutter, and run on one cylinder. Really noticeable if you roll the accelerator hard. Have started at the fuel pump in tank and replaced stock line with a better line, no fix. Replaced Plugs and fix. Discovered an intake leak, replaced with new gaskets/rings and cleaned injectors using a Fuel Injecter ultrasonic (or whatever the thing is called) machine, fix but the bike ran way better than before but when got up to hot, same problem reoccurred. I am down to now having to take it to dealer for diagnostic test on Coil and ECM. My indie mechanic who helped me said he thinks it may be coil but the Harley Tech he spoke with said it sounded like ECM...And he did not have the equipment to test the coil but we did notice the coil got really hot...

    Good luck with your issue and I hope you discover the fix. If it is the ECM, I may look into a Thundermax (or similar product) replacement, will need to get some opinions on that too as the cost is about the same and it is straight plug and play.
  3. dbmg

    dbmg Experienced Member

    There has been issues where as a piggyback fueler that is to trick ECM into providing better performance with bike has been damaged or rendered useless and does not operate properly..
  4. bcortani

    bcortani Active Member

    I had been running the Dobecks Gen 3...I know Dobecks is a stand up company, how is thier customer service regarding the possibility thier product damged my ECM?
  5. TQuentin1

    TQuentin1 Well-Known Member Staff Member Moderator

    I would suspect a break in the wires to the injector(s). Especially since you say the front cylinder is not firing consistently.

    If you can get it running and before it gets too hot, reach in and wiggle the injector wires where they mate to the connector. See if you notice a change in ignition which will be fuel to the cylinder. This will confirm that is your problem. See here:

    Harley Davidson Forums

    To fix this, it is easiest to remove the tank, but you may be able to get enough room by tilting the rear of the tank up. BUT BE CAREFUL THAT YOU DO NOT DAMAGE THE TANK CONNECTIONS. Tilt it slowly while checking for things binding.

    Let us know.


  6. whitebuell

    whitebuell Member

    I tried the wiggle test, nothing seems wrong.
    Tried the resistance test with a break out box to the injector leads and that all seems fine.
    The injectors spray the right amount and time but still no fire in the front cilinder.It started as a slight hesitation and got worse over time, no it happens when we start the bike and it stays that way. the lead from the ignition to de front and rear injector line is ok, the other one comes from the ECM to the injectors and I think there is the problem,I think the ECM does not give the right command to the front injector.
    I do not use a piggy back box but the Direct Link,that is software that you put in the OEM ECM,I don't have the program or software from those guys.
    When I have the rear sprak plug out, it fires but very low and the bike does not turn on his own, it runs on te starter.
    When I have the front spark plug out ,the bike starts and runs on one cilinder.
    Keeps throwing the front injector faulty code .
    Normally I should have 12 V on the injectors with ignition on after 2 seconds, that does not happen to both of them, that worries me and points to the ECM being bad.I keep you posted on the problem.
    If the ECM is bad, I am going to put a thundermax closed loop system on the bike ,but I have to be sure the ECM is faulty.
    I going over the whole test again and see what happens today.
    Thx for thinking with me.
  7. pinnball

    pinnball New Member

    I would check the coil.when the coil goes bad it acts up when it gets warm.
  8. whitebuell

    whitebuell Member

    I changed the coil,sparkplug wires and sparkplugs, nothing wrong with them , it is seems the signal ,also checked with a stroboscooplight, the pulses are normal.
  9. whitebuell

    whitebuell Member

    Wel this seems the same problem as I have,and it started the same way .
  10. Bodeen

    Bodeen Well-Known Member Staff Member Moderator Contributor

    Not sure but does this bike have an engine temp sensor? If it does, I am thinking if it were bad the bike may be in a permanent limp mode? May be something for you to check...