Could the boots that are on each side of the terminal block be leaking, maybe damaged when things went south from before, you did clean them up? You mention a new dis cap so that's out. That black wire looks like it is ground and attached to the rectangular part of the coil. If I am looking at the picture the right way, makes sense a leaking wire would be flashing all around that area. As Charlie says run it in the dark to isolate.