Ignition problem (no spark on number three cylinder)

[Guyver]

I'm back and still have my bike. Things have been quite crazy in my life for some time and now I find myself trying to fix this problem with my 1984 GS1150ES. The bike fell over once and damaged the ignition cover and other unassociated things. Days later I was riding the bike home and it lost power and then died and would not restart. I had it towed home and it sat in the garage for months.

I isolated the problem as no spark to the number three cylinder and thought it was the coil. I bought some green coils for it and new Superstock wires as well. The bike starts and runs; however, it still does not have spark on number three. I traced the wires through the harness back to a connector and there are no shorts. The wires then run to the Dyna S ignition module. Could the module crapping out cause this problem?

[renobruce]

#2 fires, but #3 doesn't? They should both fire at the same time. Bad plug?

[Guyver]

Hey Reno!

Hiya Reno, I have a spark tester that runs inline between the plug wire and the plug and it lights up to show that spark is reaching the plug. On cylinder three, the third cylinder to the right as you're sitting on the bike, I get nothing. The other plug wires show a spark is reaching the plug. The green coils have two connectors each for the wires, not the plug wires, to the coil and they are not marked positive or negative like the original coils were. The bike runs on three cylinders so I assume that the wires are hooked up properly.

[renobruce]

Try disconnecting the dyna s output wires and reconnect them in reverse. If the spark problem transfers to the opposite plugs, it indicates a bad power module. If they stay with the same plugs, it indicates a bad coil, or a problem in the wiring.

[renobruce]

On a side note, what's up with the bike? Did the buyer back out? Are you keeping it?

[Guyver]

Thanks again Reno

I'll check the wires out. Meanwhile the buyer has yet to pick the bike up. I haven't put any miles on it and if he can't get it by the end of the month I'm keeping it and giving him back his money. ~Gene

[renobruce]

I'll check the wires out. Meanwhile the buyer has yet to pick the bike up. I haven't put any miles on it and if he can't get it by the end of the month I'm keeping it and giving him back his money. ~Gene

I hope you get to keep it. Sure is nice!

[Nessism]

The Dyna S fires the coils in pairs; one pickup is for 1-4 and the other for 2-3. If #2 plug fires but #3 doesn’t, it indicates either an internal coil problem or a spark plug cable problem, not a Dyna S or a wiring problem. Sounds like you should try replacing (or swaping side to side) the spark plug wire for #3 and see if the plug starts firing. If not, the problem is most likely the coil itself - internal failure.

Good luck.

[salty_monk]

Had the same on mine... coil problem (on a 13month old Dyna S). They replaced it under warranty.

Dan