OK guys i have a 74 duster with a 440 i have no spark coming from the coil so i replaced the ecu .. still no spark .. so i said what the hell replaced the coil still no spark... i have 12 v at coil until i conected it to the coil then i have 4v .. the question i have does the ballast resistor can it cause you to have no spark .. if so i will replace ..... if not any ideas i am at a loss