Ok ' If we go back to the basics, The coil develops its high voltage by energizing the primary winding. The period of time this is energized is called coil saturation or dwell. This builds a magnetic field that when the circuit is opened the field collapses to the secondary winding which in this case provides high voltage to the distributor cap. Excessive resistance in the primary circuit can reduce the secondary voltage produced by the coil considerably. So a bad transistor(coil trigger) in the ECM could in fact allow a weak spark at the coil wire, but will not be able to bridge the rotor gap.
Conner