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Ignition spark randomly dropping

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Old Apr 29, 2019 | 08:53 AM
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Default Ignition spark randomly dropping

If I didn’t shave my head I’d have it all pulled out at this point. I have a 91 flhtcu 80” carbureted. The bike is dropping spark (only way I know how to explain it) randomly. Becoming more often now but just looking for advice. Replaced plugs, wires and magnetic pickup (cam sensor) at this point. Coil seems to be fine based on resistance check. Will the ignition module cause an issue like this? Thanks for any input in advance.
 
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Old Apr 29, 2019 | 09:02 AM
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Could the coil be bad randomly but still test ok on the ohm meter?
 
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Old Apr 29, 2019 | 09:55 AM
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Originally Posted by Bcoish
Could the coil be bad randomly but still test ok on the ohm meter?
It could, I know texashillcountry (thc) had that problem...
 
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Old Apr 29, 2019 | 09:57 AM
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I’m getting a different coil to try tonight from a buddies shop. I hope that’s it.
 
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Old Apr 29, 2019 | 10:01 AM
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Originally Posted by 98hotrodfatboy
It could, I know texashillcountry (thc) had that problem...
Thanks, I hope that’s it!!
 
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Old Apr 29, 2019 | 01:22 PM
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You know on an older bike it can be as much as a poor connection somewhere in the ignition circuit.. have you checked all connectors? Jiggle test... I just recently lost all accessory lighting. Circuit breaker was constantly tripping. Found an intermittent short in the harness that was shorting to the rear tank mount....
 
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Old Apr 29, 2019 | 01:31 PM
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Originally Posted by 98hotrodfatboy
You know on an older bike it can be as much as a poor connection somewhere in the ignition circuit.. have you checked all connectors? Jiggle test... I just recently lost all accessory lighting. Circuit breaker was constantly tripping. Found an intermittent short in the harness that was shorting to the rear tank mount....
I thought of that but don’t think it’s the case as I rebuilt this thing over the winter and pretty sure all connections are solid but going to check today.
 
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Old Apr 29, 2019 | 03:09 PM
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I had something like happen to my 85. I replaced everything in the ignition....I thought. I was looking thru the schematic and saw the 15 amp ignition circuit breaker was the only thing I didn't replace. I replaced it and my problems stopped. they should be under the speedo/tach head. I think there is 4, 15 amp breakers on your model. I replaced all of mine while I was in there. I got mine at an auto parts store but that was before amazon came along.
 
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Old Apr 29, 2019 | 03:29 PM
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Originally Posted by bagga
I had something like happen to my 85. I replaced everything in the ignition....I thought. I was looking thru the schematic and saw the 15 amp ignition circuit breaker was the only thing I didn't replace. I replaced it and my problems stopped. they should be under the speedo/tach head. I think there is 4, 15 amp breakers on your model. I replaced all of mine while I was in there. I got mine at an auto parts store but that was before amazon came along.
thanks, hopefully the coil fixes it. If not I’ll dig in there. Very frustrated at this point!!
 
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Old Apr 29, 2019 | 07:01 PM
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So my VOES ground was very loose, as in the screw was barely in and the connectors were hanging on the screw but not tight to the frame. Could this be possibly the issue?
 
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