07 Deuce firing on one cylinder and blows ECM fuse

Discussion in 'Electrical' started by ElGordo, Oct 10, 2012.

  1. ElGordo

    ElGordo Member

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    2007 FXSTDI Softail Deuce.
    14,000 miles.
    Vance and Hines Big Radius Duals
    Kuriyakin Hyper charger with K&N filter
    Power Commander

    Anyone know how to tell if it's the coil? And if it is, would that cause the ECM Power fuse to blow? First problem I've ever had out of it since new!
    It is a single spark coil. I checked and there are 4 wires at the plug.

    What i have done so far:
    Put it in diagnostic mode to check for codes
    P- None
    S- U 10 16
    SP- U 10 16
    T- No resp (does not have a tach)

    Cleared codes and replaced fuse. Bike starts but you can clearly tell its only running on one cylinder. pull spark plug wires and determine it is the rear cylinder not firing.
    For good measure I also changed the plugs since it was time anyway. As I suspected, it wasn't a fouled plug.
    Also you can smell unburned fuel which I suspect is coming from the rear cylinder. Hopefully that means the injector is fine.

    Interesting note, it will sit and run (albeit rough!) no problem. But if you try to rev the engine, it blows the fuse and dies and resets the code on S ( U 10 16) every time, SP gets the code only sometimes.

    I have the shop manual with schematics.

    Thanks in advance!
     
  2. ElGordo

    ElGordo Member

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    And I almost forgot to thank Jack Klarich and Hoople for the info on putting it into diagnostic mode and clearing the codes!
     
  3. cdn-bigfoot

    cdn-bigfoot Junior Member

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    working backwards after testing the spark plugs I would check your spark plug wires.
    Old school.
     
  4. Hoople

    Hoople Account Removed

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    Since the Power Commander is between the ECM and wiring Harness, you must temporarily disconnect it and leave it out of the picture. Once the issue is resolved, you can connect the PC back up but for now, I would disconnect it..
    U1016 is serial data issue, probably because of PC
     
  5. ElGordo

    ElGordo Member

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    Roger that, I was wondering about it and didn't want to do that until I found out for sure. Will I have to re flash the PC when I reconnect it? I was told yesterday by a mechanic in a bike shop that I would have to if I disconnected it. Not a big deal if so.
    Thanks for the info! I have actually been scouring this forum for days trying to get a clue on this. Seems to be a pretty knowledgeable bunch of folks here.
    Will do this when I get home today!
    Thanks again!
     
  6. Hoople

    Hoople Account Removed

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    I seriously doubt it & have never heard of that before. That would mean every time you disconnect the battery or removed the Maxi fuse, you would have to reflash the Power Commander. That would be crazy.

    The Delphi 4 wire coils that are used on these late model bikes are pretty much bullet proof from what I can see.
    If yours is bad, it will be the 1st one I have heard of that went bad.

    When you unplug and re-plug those large 36 pin connectors be careful that you do it "straight" and not to wedge the connector.

    Once you remove the PC, clear the error log of any DTC codes. Start the bike and see if it runs on both cylinders. If not, give it a minute of running time in order to collect a DTC code.
     
  7. ElGordo

    ElGordo Member

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    OK here's the update:

    Ensured all codes were cleared out, disconnected Power Commander and connected stock ECM connector into stock ECM.

    Now firing on both cylinders, can rev motor up and doesn't blow fuse! Ran for about 10 minutes revving occasionally and just ran like a champ.

    For arguments sake, since i had just washed her the day before all of this happened, I reconnected the Power Commander. Just in case it was some water in a connection or something. Well it went back to running on one cylinder. Didn't bother revving it up at this point to see if it would blow yet another ECM Power fuse. Disconnected and reconnected as before and running on both cylinders off the stock ECM.

    OK, think we've got it narrowed down to the Power Commander, heres the next question. Is there a better module out there than this? Up front, the primary selling point on the PC was that I was told that it would not void the warranty like the Screamin' Eagle module. (Which still makes as much sense now as it did then!) Now, 5 years later, that's a non issue. I'm probably opening up a Pandora's box of opinion here but I cant help but ask; what is the best module to go with?

    And just in case I havent said it enough, thanks for all the advice! Hopefully I will be able to lend a hand one day myself!
     
  8. ElGordo

    ElGordo Member

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    oh and no codes at all running with the stock ECM setup after 20 minutes! Sorry, I know that was one of the things to check. Forgot to note it. Also checked the pins on the PC connector and no bent or burned pins. Everything lines up!
     
  9. Jack Klarich

    Jack Klarich Expert Member

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    Good deal on fixing your problem, a bit of dilectric grease on your connections will make them water proof, as far as better TFI http://www.hdtalking.com/archive/t-7786.html have a :slook here
     
  10. ElGordo

    ElGordo Member

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    Ok so would mine be the softail, or softail high compression?