Back story tells me it is either a failing Ignition Control Module or crank sensor.
Not directed at you, but I wish everyone would go out and buy and extra coil pack/ICM, try it and put it on the shelf. Then when something like this happens one can try the back stock ICM/Coil Pack and isolate the issue to the crank sensor.
The problem you now have is that you are buying used ICM/Coil Packs and are unsure if they are any good which complicates your testing.