could be oil from valve cover gasket or not changing plugs wires
Leaking valve guides in the head will cause oil to get around the spark plugs.
It is black.
It may be that the spark plug is dirty. Try cleaning it
No spark.
friction
No spark from coil, bad plug wires, or bad plugs.
ummmm you fried it
if the spark plugs are black because your car is running too rich. your plugs are fouled.
Time to replace seals, this usually causes misfire.
If you touch the sparky thingy that could cause a spark through your body which would be a bad spark. Am I close?
Check the spark plug wires and spark plugs.
bad spark plug wires, low battery, broken rotor in the distributor