After fighting a misfire in my pace car, I've pretty much decided it's probably my MSD ignition....either the distributor or the 6AL box. So I decided to go back to the duraspark 2 setup. I robbed the ignition harness off my 79 cobra. The distributor looked ok, but the ignition module was beyond roached. So I picked up a new one from the parts store. Afterward, I found that I also had another brand new one...don't recall where I got it, but I believe it is BWD brand.
My car has an aftermarket Holley electric fuel pump...302 with holley carb. I plugged in the harness and hooked everything up. I'm using an aftermarket ignition coil...I have 3 of them lying around. After hooking up the duraspark system, the fuel pump wouldn't kick on. I checked the relay with my meter and it was only getting 5 or 6 volts. After some poking around, I found that the coil was getting very hot with the ignition in the run position (engine off). Some more poking around under the hood, and I found that I could unplug the 12v wire from the module and my fuel pump would have 12v again...coil not getting hot, but of course, I had no spark. I found that I could get the fuel pump to kick on by unplugging the module and then plugging it back in. As soon as I unplug the 12v supply wire to the module, the fuel pump will kick on (key in "run" position, of course). If I plug the module back in, I can hear the fuel pump bog down, but it will stay running. Car will then start up and sounds like it's running great. But coil will still get hot and fuel pump relay is only getting 5-6v. Obviously, something is grounding out whenever I have power to the module.
I tried different coils, both modules, the old distributor, and even removed the old harness and wired each connection individually...going by wiring diagrams I found online and in my manuals. Nothing helped.
At this point, I'm at a loss. Oh...and I tried running separate 12v wires to the coil and module (straight from battery) and even installed a separate 12v wire (with and without a ballast resistor) to the coil.
Any help or suggestions would be appreciated. Thx!
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