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Nagging issue with starting circuit

XS22J8R

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I've had an issue with my '78 Magnum when starting it. It's a 360 4 barrel, all the lean burn gadgetry is gone.
Often when turning the key to start it, the starter cranks but nothing happens, not even a hiccup. Though when turning the key back out of starter mode it will often hiccup briefly just before the key hits the off position.
After 3 or 4 attempts the car will usually fire right up. Once running its fine. But after turning it off all bets are off if it will start again. It used to be it would be usually be fine when first starting up in my garage but after going to a car show or something it would fight me trying to start it up to go home, so I thought maybe hot weather had an effect on this.
I replaced the ECU but that didn't help. Some suggested the ballast resistor (4 prong), and at a cruise in July when having the problem a friend brought over a spare one and we plugged it in. Car fired right up. I shut down, then plugged back into my ballast resistor and it fired up first try.
I then got a new ballast resistor and installed it, but same problem still happens.
I find now when it won't start, I can unplug the ballast resistor, then plug it back in, and then the car will start right up at the first try.
I'm pretty much of a moron when it comes to diagnosing electrical issues. Would this indicate something bad with the plug, corrosion, a bad ground perhaps?
I always manage to get the car started eventually but I worry at some point the tricks won't work. And I'd like to get this issue resolved because otherwise the car behaves great and is super reliable!
 
I would start looking at the wiring near the resistor. The resistor is probably good, but just the act of unplugging it and plugging it back in is moving the harness enough that a potential open in the wires is being fixed.
 
Perhaps you need to tighten up the connectors that plug on the ballast.
See if there is corrosion where they are crimped onto the copper wire.
They should be able to be removed from the housing and given a squeeze with some small pliers to fit tighter.
Otherwise it may be back further at the bulkhead.
I doubt it's a bad wire but it's possible.

I would first do some checking with a volt meter at the ballast.
Disable the starter relay and have a helper move the key to start and run position.
Maybe try it cold and then hot/warm.
 
Based on what you describe, it sounds like your ignition switch inside your column is worn out (the electrical contacts damaged).
 
Sound like you eliminated it being the ballast resistor by replacing it. IMO those ballast connectors are suspect as @Don Frelier suggested, as it works instantly once the wires are unplugged and plugged back in. Work your way back to the keyed power source from there.
 
While the issue sounds like what's been posted for fixes - I had a bad ignition wire connection at the BH that looked fine until closer look, just thinking if your gear shift position might be involved? You may have tried moving it to N and start and/or jiggling the shifter in P? If not, something to rule out. Doesn't sound like the hassle; but easy check.
 
I've had an issue with my '78 Magnum when starting it. It's a 360 4 barrel, all the lean burn gadgetry is gone.
Often when turning the key to start it, the starter cranks but nothing happens, not even a hiccup. Though when turning the key back out of starter mode it will often hiccup briefly just before the key hits the off position.
After 3 or 4 attempts the car will usually fire right up. Once running its fine. But after turning it off all bets are off if it will start again. It used to be it would be usually be fine when first starting up in my garage but after going to a car show or something it would fight me trying to start it up to go home, so I thought maybe hot weather had an effect on this.
I replaced the ECU but that didn't help. Some suggested the ballast resistor (4 prong), and at a cruise in July when having the problem a friend brought over a spare one and we plugged it in. Car fired right up. I shut down, then plugged back into my ballast resistor and it fired up first try.
I then got a new ballast resistor and installed it, but same problem still happens.
I find now when it won't start, I can unplug the ballast resistor, then plug it back in, and then the car will start right up at the first try.
I'm pretty much of a moron when it comes to diagnosing electrical issues. Would this indicate something bad with the plug, corrosion, a bad ground perhaps?
I always manage to get the car started eventually but I worry at some point the tricks won't work. And I'd like to get this issue resolved because otherwise the car behaves great and is super reliable!
Yes, sounds like it could be a ballast resistor issue.
 
The two prong connector to the distributor could be the cause. Pull the coil wire and turn the key on. There should be 1 spark. If so, ballast, ECU, and coil are fine. Distributor and reluctor are then suspect.
 
Thanks for all the ideas! I don't even have a functioning volt meter right now, but I will see if I can get my buddy over with his to spend a little while troubleshooting with me this weekend!
 
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