[mr0077]

h dog, sounds like you have the coil wired up using the wire intended for the ballast resistor. When you use a ballast resistor, turning the key to the start position (during cranking) sends full battery voltage to the coil (appr. 9-10 volts). Once the car starts and you let the key go to the run position power isswitched through the ballast resistor, which drops about 3 volts and sends 9-10 volts to the coil. You could check to see if you have battery voltage to the coil in the run position, I bet you don't, but you will have it in the start position. If this is it, try hooking both the ballast and the normal coil wire to the coil and see if that solves the problem. Another place to look is the ignition switch, make sure you have the coil and ballast resistor wires on the right terminals.
Good luck.