i have 12 volts to coil but seems like sometimes i lose spark to secondary is the 12v circut should always be engerized when ign on or does circut opening relay control some of this seems to be a got spark then no spark problem really wierd p. replaced a dist comp so both cannot be bad
any help appreciated

 

With ign switch there should be 12V at the + terminal on coil

Voltage on other coil DC power terminal would cycle on/off and be controlled by the igniter.

The circuit opening relay controls the fuel pump on/off. If the engine is cranking or running the relay would be closed and the fuel pump running. The relay does not control power to the coil.

The distributor would tell the igniter when to power the coil. This would be based on the location of the reluctor ring that is inside the distributor. There are sensor inside the distributor that pick up the reluctor pulses as it rotates.

Have you checked the coil?

 

turned out to be the gear at bottom of the dist came loose
so in effect the shaft on dist froze i had a older dist and it brought car back to life mnow on to smog ca which is always fun thanks to all she is an old toy but dang she keeps plugging away
again thanks all

 

That would do it.

 

purring fine with the new mods