I have a 2015 Briggs 37 EFI That is causing me to lose what little hair I have left. For the first 40-45 minutes it ran great. Suddenly it dropped to idle for a couple of minutes then quit completely. After troubleshooting I discovered the starboard coil had ruptured and part of the coils internals were hanging out. This was entirely new to me and I figured the coil was defective. The coil was replaced and run several minutes in the yard with no problems. The next time on the river I made it about a mile and the engine quit. After removing the cowling I found another exploded coil. I'm not big on coincidences so I doubt I got a second bad coil. something is causing the coil to self destruct. I've searched here and on Google with no luck. The wrenches on here are a lot smarter than me so hopefully someone can come up with a cause and corrective action. I took a picture of the coils and the damage to both is almost the same. The engine has a whole 55 minutes on it.

I don't know what it "should be" but I'd check the voltage the ECM is sending. Just compare one side vs the other. I'd also go over all your grounds for starters.

Thanks for the input, Longtail. I have the EFI service manual and I'm keeping your advice in mind at each step of the troubleshooting procedure. It is hard to duplicate because it keeps blowing the 20 amp fuse in the fuse block. I haven't found anywhere in the service manual that says if the 20 amp fuse blows and the starboard coil explodes... do this. Obviously, too many amps are coming from somewhere, but that is hard to narrow down if it won't run. I'm thinking ECU, voltage regulator, or wiring harness. I dislike troubleshooting by replacing parts, but it may come to that if I can't find an obvious defect. I was hoping someone had seen this before and could shorten my search. All of the mudmotor factories are closed for the holidays and I plan on phoning some of them this week. When I nail it down I'll post what I find.

I was thinking about voltage also, another long shot is the crank sensor too far from flywheel giving a weired signal

.030" on CPS to flywheel. Its there just to tell the ECM where the position is. That is all. The coil is energized all the time and the ECM grounds it to complete the signal. I would request a new updated harness and replace it. You more than likely have a wire chaffed somewhere. Most of the ECM operates on 5V but some is 12V... I'm just speculating, But replacing the harness is one good starting point.

Maxxis is a pretty fart smeller, he is.

No problem. I try Something like this is hard to do over the internet, But knowing Stu's Mechanical Aptitude, he can do a lot for himself.

As for CB, well that fart sniffer can lick crayons lol