[nepatfn]

Hello guys, trying to get my 73 smallblock electronic ignition system figured out. Cannot get spark, check coil and only getting 7.36 volts. Verified getting 13v at the bulkhead connector ignition run pin 23 and 7.36v ignition start pin 22. My question is what should I have at the coil positive and on pin 22. What could be causing this issue. The weird thing about this is I had the car running a week ago after installing a new wiring harness but decided to put a new edelbrock performer carb on it. Now I get no spark So much for a quick carb upgrade... I guess its a good thing I have the fenders off getting painted. Would hate to have this problem if the car was able to drive...
Thanks
Mike

[dave-r]

You should only have 12v on the coil +ve when cranking. The rest of the time you have a lower voltage that depends on what ballast resistor you have fitted. I don't think it should be as low as 7v though?

Even so you should still get some spark at the end of the coil lead. If not the coil or lead is buggered.

[nepatfn]

Thanks for the quick reply Dave.
Wires, pick up coil, cap & rotor, coil and ballast resistor all replaced prior to carb swap.
So i should have 12v on coil positive when cranking and a lower voltage when key is on. If not 12v when cranking what then?

[nepatfn]

Voltage goes up to 8.65v when cranking on Ve+ on coil. Bud Ignition control unit? I used the info on this mb to check voltage and resistance of the wires and it looks to be in spec.

Now what?

[nepatfn]

Replaced ignition control unit ... Now to the body man for my fresh fenders....
FYI voltage still 7.36v on ve+ side of coil with key on but goes to 11.32 with key to start...

Thanks for the help Dave.

Mike