'70 GTX Ignition

[70plygtx]

Hello,

Let me first say that wiring is not my forte.

I have a 1970 GTX, will not stay running. I have noticed that it dies as soon as you let off of the key (the starter is not staying engaged). Checked all fuses (that I know of), all check out OK.
Any ideas? Anything is greatly appreciated.

 

[kiwigtx]

Have a check of the bulkhead connectors and plugs, also the long flat white plug & connector from the steering column (under the column) and maybe carefully use some spray contact cleaner n the terminals. Usually just a dirty connection can cause this to happen.
If you can post some pictures of your car - and engine loom, it would e helpful. :hello2:

 

[miller]

Check, or replace your ballast resistor. Get a good one. I've gotten some that last one hit, and go bad!

If that's not it, could be the ign switch itself.

 

[mopar 3 B]

Do not replace anything till you know what went wrong. If you do not have one buy a voltmeter and start checking from blasit to the ignition switch. But if it is running in the start mode and not the run the ignition switch is more than likely bad.

 

[SlinktRR]

Could also be the ECU if you are running electronic ignition, but ballast is possible as in "start" mode the ballast is bypassed completely. Like mopar3B said, get a meter and start looking at the circuits to and from the ballast resistor, ECU and coil. Meter helps a lot with these kind of ignition issues. It should show full 12V at the coil when starting and then drop to 9-10 when off the key (in run). When I encountered this the orange box ECU was the culprit. I have been using the gray NAPA box since and it's been great. Still carry a spare in the trunk...

 

[70plygtx]

Thanks for the recommendations. I will let all know my findings.