Ignition Issue, motor wont stay running

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wes beem

wes beem

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71 Duster, Got a 360 magnum swap, hei dsitributior factory collumn, carbureted.

Motor fires right up as soon as you turn the key to engage the starter, but if you let go of the key it instantly dies.

If you hold the key in the start position the motor will keep running as long as you hold it....

Any idea what wires might be switched/crossed?
 
If the wiring is correct, then the ignition switch is bad.

You need to get a wiring diagram and trace out the wires to see the route it takes from the switch to the ignition is intact.

Another posable cause is the ballast resister.

If it is broken it will produce the same result.

A quick check is to run a jumper around the ballast resister, if the car starts and keeps running the resister needs to be replaced.
 
Check for voltage with both ballast leads disconnected...........

1679529536335.png
 
Daves69 said:
Check for voltage with both ballast leads disconnected...........

View attachment 1716067345
Click to expand...
AGAIN I disagree. Check voltage with ALL WIRING CONNECTED

WHY? Because often a LOAD (the ignition, VR, generator field) will help to expose a bad connection, where instead if you disconnect the loads, the voltage can appear normal
 
VERY SIMPLE

DID IT EVER RUN or have you recently made modifications?

Find a way to bypass the ballast resistor if it is still there.

If you ELIMINATED the ballast, the old ballast connections MUST BE JUMPERED to get it to run

Clip your meter to the coil + and ground
Turn key to run. You should see somewhere around 6--10V but not much higher.

If not, get under the column, access the column wiring connector and check the "run" IGN1 wire at the ignition switch connector.

Could be something bad in the ignition switch, switch connector, bulkhead connector, any of the wire terminals along the way, or the BALLAST resistor itself

The path for the "run" wire is from ignition switch, through the bulkhead connector, and to the ballast resistor. A splice there nearby also powers the VR and depending on the year, a couple other underhood loads

Be cautious, THAT IS NOT FUSED
 
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dont think i gave enough info. its an HEI 1 wire setup, there is no ballast resistor or voltage regulator anymore, its gm style painless performance wiring
 
What I wrote still applies.
wes beem said:
dont think i gave enough info. its an HEI 1 wire setup, there is no ballast resistor or voltage regulator anymore, its gm style painless performance wiring
Click to expand...
There are two circuits originally. THE IGNITION RUN circuit goes DEAD when cranking. So to run without a ballast, the ballast must be jumpered across, AKA the ign1 "run" and ign2 "bypass" circuits must be tied together

You did not answer my question..........Have you had this running successfully and the problem just showed up, or did you just put it together and it has not yet run with this configuration?
 
we figured there was going to be some issue related to the collumn, the painless wiring kit Assumes your ripping your mopar collumn out and replacing it with a junk aftermarket one, so we were flying blind in the area of the ignition collumn pigtail.
 
Oh, NOW we find out. YOU HAVE TO TELL US THESE LITTLE DETAILS!!! OK, the IGN2 wire is not dealt with in the Painless kit. Either connect the two together at the ignition switch or run a separate wire out like the original. Since you "likely" don't plan to use a ballasted ignition system, the easiest way is to connect them at the column ignition switch connector.

You want to jumper the brown and blu together, 3rd from top and 4th from top

ignsw.jpg
 
HOW THIS WORKS

When the key is in the "run" position, you have two ignition switch contacts live...."run" and "acc"

When you twist the key to start, things change, and you end up with two contacts live, ONLY the 'start' (yellow) and the bypass/ IGN2 (brown) which feeds full power to the lgnition system during cranking

The "start" and "bypass" (IGN2) are live at same time but they are DIFFERENT contacts and different circuits in the switch, so don't try and use the yellow for this purpose
 
thanks! We're gonna be back in the shop Monday to try and sort it out again!
 
I'd be checking the 'run' wire at the bulkhead connector for a bad/corroded connector.
 
Dana67Dart said:
Hence why to just use an OEM Style plug and play harness.
Click to expand...
almost impossible to find that, especially when your trying to do away with weaknesses in the wiring system like those junk ballast resistors, cdi boxes, and voltage regulators that are prone to failing and leaving you stranded.

If someone made an HEI capable drop in harness id be allover it.
 
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HEI retrofit instructions are pretty much all over this forum and a few other Mopar forums I frequent with a little search action
 
Starting with a OEM style harness and modifying what is needed is much easier than trying to figure out that that wire gets spliced to that connector and that wire is no longer needed etc
 
Did some experimenting today to rule things out. We ran a wire direct from battery to the + End of the coil, Turned the key, motor fired up and stayed running flawlessly. So now we know the issue for sure is that when the key isnt in the "start" position the coil isn't firing.
 
wes beem said:
Did some experimenting today to rule things out. We ran a wire direct from battery to the + End of the coil, Turned the key, motor fired up and stayed running flawlessly. So now we know the issue for sure is that when the key isnt in the "start" position the coil isn't firing.
Click to expand...

Hence why you need to do as Del said and tie Ign.1 and Ign.2 together to power your coil.
This is exactly what the instructions said for the HEI kits I used to build for members here.
 
Wiring guy is out of town until Monday so i was just trying to rule out several other things we had suspicion it could have been in the meantime
 
67Dart273 said:
Oh, NOW we find out. YOU HAVE TO TELL US THESE LITTLE DETAILS!!! OK, the IGN2 wire is not dealt with in the Painless kit. Either connect the two together at the ignition switch or run a separate wire out like the original. Since you "likely" don't plan to use a ballasted ignition system, the easiest way is to connect them at the column ignition switch connector.

You want to jumper the brown and blu together, 3rd from top and 4th from top

View attachment 1716067388
Click to expand...
Wiring guy was back today, did exactly what you said and now she fires up and purrs like a demon belched out from Hell!!!! Thanks!
 
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