my 72 newport is not geting spark all of a sudden what can i do
Check the battery voltage, the wiring for a short to ground, and distrbutor.
Test for voltage to the coil with the key on, if there is voltage with key on then test for voltage cranking, if you have voltage your ballast resistor is good, if no voltage then the resistor is bad or there is no power to the resistor block and you will have to trace down the circuit. You didn't state if you had solid state ignition or point type. So the next step is to check for a trigger pulse to the ignition coil, put a test light on the negative wire on the coil and a good positive power supply and crank the engine, the light should flash, if it doesn't then replace the the points and condenser if equipped that way or the solid state control spark module and retest, if the light flashes when cranked it should start and run then, if still no light then it could be the distributor pickup coil or again bad wiring. Spark modules and resistor blocks were high failure units on these old monsters if it had solid state ignition. The other earlier years was ballast units and points and condensers. HTH