Recently removed the heads on my 383. Put everything back together and now have no spark. Know I hooked up my tack wire on the positive and moved it back to the negative side of coil. Replaced the coil thinking it might be bad. Showing low voltage at the coil. Tested the ECU and it test right. Tested the distributor and it all checks out. Ballast resistor also test good. Only have about 10 volts at the blue wire on the coil not hooked to the coil. Once hooking the coil, the voltage falls. Just wonder what others might think the problem is. I did not change anything and have good ground throughout. Any ideas would be appreciated. Do have a new ECU on its way to see if a new one is the answer. Going to replace the start run relay also. Yes, have read forums and also googled the problem but too no progress. What am I missing. Thanks for input. Blue.