Can anyone explain to me how to wire the key switch ignition to get the engine to start?
Running a MSD Ignition and the car spins over but no spark, I cut a wire or 2 and cant seem to find where the cut is.
I need to get the car running.
MSD is wired correctly.

I have a 2 wire into 1 from the key switch but one black wire is cut.
I have no idea where it goes to.
I suppose I need wires going to the starter relay on the engine side firewall somewhere. I hope someone can explain it in simple form. I'm not very electrical savvy. Thanks

what car is this in?

Do you have a service manual? The service manual will have a wiring diagram in section 8 which you can use to see which wire is which.

the wiring diagrams at www.mymopar.com are somewhat complete.

So tracing the wire from behind the key switch and to the starter relay, should all terminals be hot in the on position?
I used the service manual and figured out which wires are what.
I believe the one wire at the relay is not hot with the key in the on position.

one wire is hot in "on", one wire is hot in "start". they have to both go to your msd box.

^^^ agreed, confirm the MSD/coil are both being fed in ign1 blue wire (run) & ign2 brown wire (crank)

I think this is the problem, which wire from the MSD box gets these wires?
I think something got cut.
Would these wires come off of a relay? I see a bunch of relays on a panel but when I wired up my fuel pump, water pump, and fan I didn't use these relays.I think I have 3 relays back up under the dash

it will be easiest to find the wires that went to your ballast resistor.
blue and brown. they come out of the bulkhead connector on the engine side.

those wires tied together and connected to the keyed 12v wire on the msd should work.

Thanks I will report back to you. This is a great help.

sammy, how many wires do you have coming from your switch ? you should have at least five.

1-12v to switch [usually red]
2-ign. #1 [usually blue-run]
3-ign, #2 [usually brown-12v to coil in start]
4-accessory [usually black]
5-start [usually yellow-to starter relay]

hope this helps.

This is correct.
Yes
Black wire to accessory was cut a long time ago.
Yellow has no power in the on position.

1st I want to thank you for all your replys and help!
I traced the two wires Blue and brown from the engine bay bulkhead and it was spliced into one with a red wire that went through the firewall into the cockpit under the dash and low and behold the wire was cut and it went to the 12v switched wire on the MSD box. The car fired right up without a glitch.

You guys are the best and I'm very appreciative for all the help I get on this board.

I'm actually going through this very issue with the 72 Duster now.
I installed the MSD system (all plug and play) MSD Box...coil and distributor.
I wired everything up temporary to do the break in and everything worked with no issues.
I had to rebuild a steering column and convert from Power to manual so I bypassed everything to break the motor in.
NOW when I'm wiring everything up complete I have the yellow (Start wire to starter relay) wired up with no issues.
The large Red hot for the MSD to a battery hot...
Black to ground...
Msd run hot wire (Red) tied into the Blue (ignition 1)
Here is where I'm wondering why I wouldn't tie the brown wire into the yellow wire and pic up ignition 2 when the switch is in the start position?
Is there a downside to having the brown wire tied into the blue (ignition 1) all of the time?
Why couldn't it also be tied into the yellow where it only receives juice when the ignition is in the start position?
Just an FYI the Solenoid is a Ford unit and is behind the dash along with the MSD box. The only wires I use through the factory pin connectors are the (purple) engine temp wire and the Black Alternator wire. The alternator is a one wire unit so all other wires are terminated at the pin connector.

as i understand it, MSD systems require the brown and blue wires to be connected all the time because the ballast is bypassed, and the coil requires 12volts at all times. if you connect the brown wire into the yellow wire at the relay, it would only get 12volts at start [when the starter is engaged. not sure on the ford relay. is it a one or two post unit ?

Everything original under the hood was bypassed. The brown...blue and all wiring to and from the ballast resistor and the voltage regulator. All wires were terminated at the Firewall plug.
The coil is being powered directly by the MSD Box. The constant 12 volts would be supplied from the blue wire (Ignition 1)that is tied into the MSD (Small Red)...
I can tie the brown in with the blue but I wasn't sure if it would hurt anything.
By tying it into the yellow I knew it would only have 12 volts while cranking...(ignition 2)
In reviewing a few diagrams I think it would work either way???
The Ford starter relay has two connections but allows for 1 large wire to run to the starter while having both terminals on the starter crossed with a metal plate. This wire is only hot once energized by the yellow wire attached to the relay.

if ign1 is the only wire feeding the MSD turn on lead then your only going to have the MSD fire when ever ign1 is hot. it's either when cranking or when in the run position.
the MSD wire needs 12v during the crank and run positions. I would just wire both ign1 and ign2 to the MSD turn on lead and move on...

Exactly correct.

You could also put a hidden switch in the brown wire as sort of an antitheft device.

For someone who asked whether the MSD coil was hooked up to power, the coil is only hooked up to the MSD box. That is where the coil gets its energy, from the capacitor in the MSD box.
The coil needs to be grounded, in order to have a complete circuit from coil thru distributor rotor, plug wires, plug, across the gap, into ground, back to coil..

R.

Brown tied to Blue hooked to Red works for me...Thx all...

I ended up connecting the blue and brown wires to a bus bar. I connected all of my 12v switched items to the bar as well. Works great!