Does Anyone See An Issue With Splicing Ign 1 & 2 at Harness?

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frumharlem

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Good morning,

I have been battling issues with getting my MSD 6 AL back up. I bought a new box and was running fine for about 4 days. Yesterday, I was driving and felt a skip for a second. It happened twice, and I shrugged it off as maybe a carburetor blip. I got on the Interstate and before the 1st exit she died. It will crank and combust for like 2 seconds, or as long as you keep the key cranking. I called MSD support and the short term fix is to direct wire the small red to the battery, and cut off engine by disconnecting that wire.

Somewhere, in the engine bay, the Ignition 1 and Ignition 2 wires are not retaining continuity. I redid the solder butt connection (Ign 1/2 and thin red MSD) and still had the issue.

My thinking is that to avoid all, should I try splicing the Brown and Blue wires (Ign 1 and 2) right at the harness under the dash?
I know certain wiring makes the coil charge all the time and I don't want to cause issues with the alternator. But, not sure if this will do either of these things.
 
Other than your starter will keep cranking when the key is in the on position, no...
 
I have been battling issues with getting my MSD 6 AL back up. I bought a new box and was running fine for about 4 days. Yesterday, I was driving and felt a skip for a second. It happened twice, and I shrugged it off as maybe a carburetor blip. I got on the Interstate and before the 1st exit she died. It will crank and combust for like 2 seconds, or as long as you keep the key cranking. I called MSD support and the short term fix is to direct wire the small red to the battery, and cut off engine by disconnecting that wire.
Holley/MSD gave you an answer, but its not a great one.
It would be a useful way to test whether the problem is in the Ign 1 circuit.
So, yes I would do that as a test. Don't have to drive it anywhere. Just see if it will fire up. Alligator clips will work...
Somewhere, in the engine bay, the Ignition 1 and Ignition 2 wires are not retaining continuity. I redid the solder butt connection (Ign 1/2 and thin red MSD) and still had the issue.
No.
It could be anywhere in the circuit.
If it fires and runs when key is in Start then the Ignition 2 wire is getting power to the MSD on/off relay (thin red wire).
If it doesn't continue to run in Run, but it does when tested as suggested by Holley, then Ignition 1 is not getting power to the MSD on/off relay.
This could be anywhere in the circuit from the key switch to the MSD red wire.

My thinking is that to avoid all, should I try splicing the Brown and Blue wires (Ign 1 and 2) right at the harness under the dash?
If the problem is in the ignition switch, this doesn't solve anything.

I know certain wiring makes the coil charge all the time and I don't want to cause issues with the alternator. But, not sure if this will do either of these things.
No. The MSD supplies power to the coil in the form of capacitive discharge from the MSD box.
The way Autotronics recommended using the original ignition wire to the coil is to power the MSD's on/off switch (thin red wire). Regardless it should not connect to the coil.
The ignition run circuit is critical for running the alternator. This is its other job. On some later cars it also powers electric choke assist and other stuff.
So if it needs fixing, fix it.
Piggy back terminals and good crimp terminals are your friends. ;)

Original MSD instructions shown here
6Al2 Box 12v Keyed source
 
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^^^^^ This.
When you turn it to run (not start) the red light on the box should come on. Jiggle the wiring and look and see if it goes out. Sounds like the switched 12V source you tapped into isn't a good one.
When I wired my MSD I ran the heavy red/black directly to the battery (constant 12V) and then the small red to a random keyed ignition source, ie:switched 12V, (I was able to use the ballast resistor).
 
The probable causes are the ignition switch, the ignition switch connector, the bulkhead connector, AND SINCE YOU DID NOT MENTION what you are working on, some years have the ill advised white molex style connector to separate the engine harness, and of course "bad connections" from spliced wiring.

IGN1 GOES DEAD during cranking. It must have IGN2 which supplies power DURING cranking. IGN2 is a separate circuit/ switch contact from the "start" circuit. IGN2 was originally intended for ballast resistor equipped cars, as it pushed full battery power to the coil+ during cranking

Don't discount it could be the MSD itself, a problem in the distributor, or even the main power feeding the MSD.
 
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