Testing coil on EFI

Discussion in 'Electrical' started by jackster, Jun 4, 2008.

  1. jackster

    jackster New Member

    3
    11
    0
    I just posted an introduction, but I really need to try to find out how to do this. I don't have a service manual, so I'm hoping someone here can help me. I have been having some battery issues lately, because I ruined the factory battery and went with an el cheapo, which was a mistake in itself. Anyway, today I was jump starting it like I do just about every day, and yes it is annoying, but after I got it running I got off, took the cables off and proceeded to shut my garage door. Well I don't have a fob for my bike yet, so I usually just get off, punch in the code and go to work. Well for whatever reason, today when I got off my bike, it decided it wanted to roll and fall over before I could get back on it, bending the (edit) out of the brake handle lever .. Well I jumped it again and started going to get on the HOV lane as usual. Everything was fine until I made a right turn to get on the on ramp and it lost power suddenly. I had someone help me try to push start it, 'cause it hadn't had a chance to charge at that time, but once it was running it acted like it was running on one cylinder or something. I went back home, barely, and proceeded to check everything out, and it seems like it really is only running on one cylinder, because I pulled the front spark plug out and nothing changed, but as soon as I pulled the rear one, it shut down. The rear cylinder is extremely hot too, so my question is if the plugs are good (replaced them today) and I think there might be a problem with the coil, how do I check it? What else should I check? I ride to work every day, so I'd like to try to get it back up as soon as possible.

    I really appreciate any help in advance!

    BTW, I did get a new battery today, too.
     
    Last edited by a moderator: Jun 4, 2008
  2. glider

    glider Veteran Member

    25,464
    108
    44
    To assume it is the coil is getting ahead of your self here. Check for spark at the end of the plug wire first and secondly, get a manual for the bike.
    If the battery voltage is less than 9 volts, the bike will not start or run.

    Have you checked for damage to a component from the impact of falling?
     
  3. jackster

    jackster New Member

    3
    11
    0
    Maybe I am, but I just want to know how to test it. I was hoping to get some help before I spent the money on a manual. The battery has almost 13 volts, so it is good. The bike starts, but like I said, sounds and feels like it is running on one cylinder. Both cylinders have compression. There is no visible damage to anything other than the lever.
     
  4. glider

    glider Veteran Member

    25,464
    108
    44
    You can test the coil, but I don't think that is the problem. Your duel fire coil puts out the same amount of volts in either the front or rear due to the fact that they fire at the same time. Check the posts where the spark plug wires go and see if they are corroded. If not hen I would replace the spark plug wires. You might have a bad wire.
    If you want to test the coil. First remove it and the wires. You have to two posts where the wires go. This is the primary side. Connect the OHM meter to them. You should get about 2.5 to 3.0 OHMs. Not he secondary side is where the spark plug wires go. Connect the OHM meter to them and you should get around 10,000 to 12,500 OHMs. Best to get the manual in any event.
     
  5. puroharley

    puroharley New Member

    1
    11
    0
    hey i did some work on my 2000 road king efi, 95 kit, cams, 51mm bc throte body, ict ecm and i was having same problem front had no spark, check evrey thing and last i check spark plug wire resisten was ok, but connection to coil wasnot making contact dont know why. Just start bike and pull wire back and will click. No more problems. efi and carb sparkplug wire that same for tc alpha?
     
  6. glider

    glider Veteran Member

    25,464
    108
    44
    Should be the same, they run the ION sensing through them so the resistance should be within parameters or it will set a code.
     
  7. dangerdan

    dangerdan Junior Member

    922
    26
    0
    Since we are on this subject.

    The wires that connect to the primary , are they polarity sensative ??

    Thanks in advance
     
  8. gs34

    gs34 Junior Member

    639
    28
    5
    You know, that is a good question Dan. I know that some coils are polarity sensitive, these are normally marked at the connection points. I am really not sure about the coils used on the new EFI bikes. Guess I'll get the manual out and take a look.
    What about it Glider, Fisher, or Doc....I'm sure all of you know?
     
  9. gs34

    gs34 Junior Member

    639
    28
    5
    I would have to say yes. There is a 4 pin connector socket on the coil. Pin A is fused power for the assembly. Pin C and D are from the ECU for the rear and front coil.
     
  10. glider

    glider Veteran Member

    25,464
    108
    44
    If you are talking about the +12, yes they are PS. If you take a lead pencil and hold it between the arc from the wire end to the plug tip, you will see if you reverse the polarity that it will flash (ark) in two different directions.:D:D

    Now I can see a few guys running out to the garage with a pencil in hand :D