TFI is the gray box that's on the distributor. But if you have spark, even when it not starting, that's a good sign that those components are working.
In addition to the no start checklist, you will want to open the ECU up and check the capacitors. The fact that it runs when power is drained, and stops after a short wire might also point to ECU issues.
But start working through this
Cranks OK, but No Start Checklist for Fuel Injected 5.0 Mustangs model years 1986-1995 A word about this checklist before you start: it is arranged in a specific order to put the most likely failure items first. That will save you time, energy and money. Start at the top of the list and work...
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