Car won’t start until key is turned back to run position

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duster731

young gun
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Mar 30, 2010
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Location
Venus Texas
Specs and recent upgrades

73 duster rewired the car with new American auto wire kit using my previous set with Msd distributor, Msd 6AL box, Holley sniper coil, eddy carburetor.

The current issue I have is when trying to start the car it will not fire up until key is released. I made sure to have both ign 1 and ign 2 wires tied together and connected to Msd box for the 12v keyed red wire. Not sure where else the problem will be since I eliminated all stock parts in the car.

I tried looking at past threads on this topic but everyone seems to have this issue while on a stock platform which doesn’t help me

Any help is appreciated. Thanks

IMG_6509.jpeg
 
You're losing your IGN2 circuit somewhere from the key switch to the ignition module.
Start at the key switch, or at least at the connector at the column. Make sure you have power there when in the "crank" position (IGN2 circuit); if not, you most likely have a faulty ignition switch or column wiring.
If you do have power there, start tracing and testing the circuit from there forward until you find the break/bad connection.
Even new harnesses aren't immune to poor connections/crimps etc.
 
Maybe just a stab in the dark but I had a similar problem with my stock electronic ignition. I checked voltages and wiring and couldn't find a problem. Someone mentioned in an old thread that the coil fires once when you let go of the key. That one spark is what was starting the engine. The issue was that the distributor reluctor gap was too large to trigger a spark at low cranking speeds.
 
You're losing your IGN2 circuit somewhere from the key switch to the ignition module.
Start at the key switch, or at least at the connector at the column. Make sure you have power there when in the "crank" position (IGN2 circuit); if not, you most likely have a faulty ignition switch or column wiring.
If you do have power there, start tracing and testing the circuit from there forward until you find the break/bad connection.
Even new harnesses aren't immune to poor connections/crimps etc.
Good info. Thanks
 
Maybe just a stab in the dark but I had a similar problem with my stock electronic ignition. I checked voltages and wiring and couldn't find a problem. Someone mentioned in an old thread that the coil fires once when you let go of the key. That one spark is what was starting the engine. The issue was that the distributor reluctor gap was too large to trigger a spark at low cranking speeds.
I saw an old thread mention that too but also don’t think that is my issue as my distributor never had a problem before the new wire harness install. Although I should still check it out just in case. Thanks
 
Confirm the MSD is receiving 12 volts switched power while cranking. Could be one of the two terminals on the switch isn't working.
 
Specs and recent upgrades

73 duster rewired the car with new American auto wire kit using my previous set with Msd distributor, Msd 6AL box, Holley sniper coil, eddy carburetor.

The current issue I have is when trying to start the car it will not fire up until key is released. I made sure to have both ign 1 and ign 2 wires tied together and connected to Msd box for the 12v keyed red wire. Not sure where else the problem will be since I eliminated all stock parts in the car.

I tried looking at past threads on this topic but everyone seems to have this issue while on a stock platform which doesn’t help me

Any help is appreciated. Thanks

View attachment 1716476518
i had the same issue, you have to run a "switched hot" to the MSD box, msd doesn't agree with Mopar electrical systems, i have a switch on a panel that i flip so the car will run, kind of a PITA but its worth it
 
The OEM blue and Brown ignition wires need to be looped together. However AAW runs out of the column plug, got to get those two together if using the Mopar igninion mechanism. Put a test light on it to make sure it's hot in start position. Get that trash can running would you.... :) I see you have them looped together. Test light it. Might be the switch mechanism at key. Probe the column connector as well.

Where is the main power wire for your MSD connected?
 
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Part-1
If the engine cranks in the "crank" position, then obviously the entire brown wire start-circuit is working.
If the engine previously ran in the "run" position prior to the swap, then obviously the entire run-circuit was working.
Therefore, I agree, that the problem must lie in how you spliced those two circuits.
Part-2
On my car splicing the brown and the yellow together, caused similar issues. I installed an aftermarket relay to send battery-power to the CDI box, triggered from both wires, and a DIODE on start side, to prevent feedback to the starter-relay; which solved the problem.
Part-3
But that CDI System (Not MSD) proved to be unreliable so I ditched it and went back to the Orange box/Accell HO coil. Ran that for a while until the Orange Box gave up. About that time I installed a Jacobs, Dash-mounted, dial-back, Ignition-Module, which has been running reliably now, for over 20 years. The big Yellow square top Coil, is amazing. It's been to 7200 probably thousands of times.

BTW
In my experience, I have found reluctor gaps from Zero to .030, on good running cars; just saying.
Personally, my distributor is over 50 years old, so the top bushing is a lil worn, and so, I set the reluctor gap around .012, which prevents it from touching the pick-up. She still goes to 7200. and she still idles down to 550 in gear, pulling herself, at 5* of Idle-Timing, achieving a sub-4 mph roadspeed. (3.09 low/3.55 gears)..
 
The OEM blue and Brown ignition wires need to be looped together. However AAW runs out of the column plug, got to get those two together if using the Mopar igninion mechanism. Put a test light on it to make sure it's hot in start position. Get that trash can running would you.... :) I see you have them looped together. Test light it. Might be the switch mechanism at key. Probe the column connector as well.

Where is the main power wire for your MSD connected?
lol. I drove it today, getting an alignment tomorrow on it.

I believe main power to Msd box is off the big stud on the mopar starter relay which worked for me before the wire harness install. I’ll have to prob the column conector and go from there. Thanks
 
Part-1
If the engine cranks in the "crank" position, then obviously the entire brown wire start-circuit is working.
If the engine previously ran in the "run" position prior to the swap, then obviously the entire run-circuit was working.
Therefore, I agree, that the problem must lie in how you spliced those two circuits.
Part-2
On my car splicing the brown and the yellow together, caused similar issues. I installed an aftermarket relay to send battery-power to the CDI box, triggered from both wires, and a DIODE on start side, to prevent feedback to the starter-relay; which solved the problem.
Part-3
But that CDI System (Not MSD) proved to be unreliable so I ditched it and went back to the Orange box/Accell HO coil. Ran that for a while until the Orange Box gave up. About that time I installed a Jacobs, Dash-mounted, dial-back, Ignition-Module, which has been running reliably now, for over 20 years. The big Yellow square top Coil, is amazing. It's been to 7200 probably thousands of times.

BTW
In my experience, I have found reluctor gaps from Zero to .030, on good running cars; just saying.
Personally, my distributor is over 50 years old, so the top bushing is a lil worn, and so, I set the reluctor gap around .012, which prevents it from touching the pick-up. She still goes to 7200. and she still idles down to 550 in gear, pulling herself, at 5* of Idle-Timing, achieving a sub-4 mph roadspeed. (3.09 low/3.55 gears)..
Thank you. I’ll check this out tomorrow
 
I believe main power to Msd box is off the big stud on the mopar starter relay which worked for me before the wire harness install.
IIRC that stud is Hot all the time, even with the key off. So, if you do this, how does the MSD know to shut off. I mean, I've never had an MSD, so IDK.
 
Confirmed I have 12v at the Msd box while cranking. No issue there, as well as the ignition switch. I did pop the distributor cap off and saw a good amount of corrosion so I’ll be cleaning that off and go from there.
 
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Feed main wire does not have 12v while cranking but does in run position
 
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