VF750f NO SPARK ON #2 AND #4

I AM AT A LOSS ON THIS BIKE
NO SPARK ON 2 AND 4
SPARK UNITS GOOD...(SWAPPED ONE FROM A SPARKING BIKE)
SAME WITH COILS
PULSE GENERATORS GOOD
ANY IDEAS OF WHAT TO CHECK NEXT
THANKS IN ADVANCE FOR ANY HELP /SUGGESTIONS

 

Heya

I wish i was there, i love this sort of stuff. If all the components are good, it sounds like (this is my guess), i'd check you have power to the coil. if it's getting 12v when the key is in the on position . then next, remember that the ecu is earthing the negative low tension side of coil for a millisecond, to make the spark. So you should be able to make a spark by grounding this (the negative side of the low tension wiring to the coil), just for the shortest time you can. Don't ground the wrong wire or you will either blow a fuse or fry the ecu. I'm starting to think i should of kept my mouth shut, but that's not my style.

If you get a spark by grounding this then there is either a failed connection to the ecu like a broken wire or a failed wiring connector or the ecu has failed. And please swap the plugs before you throw the ecu away. Sometimes it's the simple things. I've had this same problem on a car, that had a failed voltage regulator, the battery over charged and acid boiled out of the battery and ran down the battery cables till it came to an electrical connector and the acid corroded the pin connectors, i'm not say this is your problem, but yeah, sometimes it's something else that has failed that has lead to the current issue.

Please let us know when you work it out

Cheers