HELP! Randomly no spark!

Ballast Resistor ? Anyways I have seen bad or loose wires at the connectors on the Ballast Resistor

Can you bring a test light with you or volt meter inside the car , so when it does shut down , first thing your going to do is check for cranking voltage on the positive side of the coil

If nothing , go to your ballast resistor with the test light - The one connector or plug with two wires on the Ballast and check for power with the key in the run position / cranking

If your getting power to the positive side of coil while cranking

Would bee looking at the coil itself

ECU ground

Pick up coil