Yeah, 3 and 4 both work the same alone, but once you hook up the second in the pair neither in that pair fire anymore.

Both the ignition drivers onboard are MPS2222As I got from japshack. According to their datasheet they're supposed to allow a little more current than the 2n2222.. supposedly. 600mAdc vs like 500 I think is what the 2n2222 is listed at. Not sure, but yeah, this is progress so far. Getting closer at least.

 

That's weird, but good to know. Next I would check your +12V and your ground are both good. You shouldn't be getting current on the trigger. Easy to check, though. Put the trigger wire to one lead of a DMM on amp mode, and the other lead touch to the pin. It should spark, but the current should be milliamps or nothing.

 

I assume that I'll need to do that under the inverted spark test? I figure they should be seriously low current for the trigger..

 

If the trigger and tach pins reversed on just one of the cop connectors, it will ground out the trigger signal. It could be the reason you get spark with just one pair of coils on each different ingition driver, but not both.

 

Yeah, that's what I mean. Like you, I expect the current to be low. So low, that there's no reason it shouldn't be working. Maybe ampz is right. Something is funky, or it would work. Getting closer though. You should use my garage for all this. Though it was overcast this morning, so I'd have to apologize for the weather. Bring a long sleeved t-shirt!