86 Ramcharger w/360 suddenly stops running

I'm stumped here and would appreciate any tips.
I have an 86 Ramcharger with a 360. It is a carb intake and stock electronic ignition.
At any random time the engine will suddenly stop. It is an immediate
stop, as if the ignition were turned off. Most of the time it will start back up. Sometimes though it will turn over without firing. If I wait some period of time (again, length is random) it will fire up.
I do not believe it is fuel related, I have plenty of gas, I have replaced the fuel pump and fuel is coming out at the carb. The carb itself was rebuilt last year, it is a Edelbrock Performer if anyone needs to know.
I believe it is a short based on this: - I noticed smoke coming off the negative post on the battery when I tried to restart it with the hood open the other day and it wouldn't fire up (no smoke when it does start) - Fuel, air and timing are all OK, but I have not confirmed spark (once it stops it is hard to get it not to start) - The stop is sudden like the ignition is turned off - There are no "trouble" signs like knocking, stuttering, smoke, or squeals - Gauges all read fine
However, I can not verify it is a short and I have no idea where else to look. Because it acts like the spark is removed when it stops, I traced back from the coil through the harness under the hood and can't find any melting, chaffing where a wire might ground out or a connector is loose. I unwrapped most of the harness and checked for wires that may have crossed and found none. The voltage regulator, orange box and ballast resistor and their connections are all OK. The distributor cap and wires are new with my last tune up about 8 months ago. Coil was replaced last year. Battery is 3 months old, alternator is less than 2 years old.
With the engine running, I have jiggled and wiggled every wire and harness under my hood and dash and unable to get it to stop.
What am I missing? Has anyone else had a similar problem?
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You seem to be under the assumption that it is a short that is causing your problems and that could have you looking in the wrong places. It sounds more like a bad connection that is both creating and affected by heat. First, I would clean up that negative battery connection. While it is not likely the cause of your problems, it is overheating when you crank for an extended period of time which indicates a bad connection or cable and needs to be fixed before it fails and leaves you stranded somewhere. Next, I would remove the connections from the coil and give them a good cleaning and make sure that they are tight as a bad connection here (dirty or loose) can cause this symptom. I would also probably replace the ballast resistor as these can also become temp sensitive and it is an inexpensive part to replace. Check the connector going to the pickup coil in the distributor and make sure that it is clean and not resting on a heat source. If it quits again, I would feel the connector going to the electronic ignition and if it is hot, you probably have a bad connection there. I would also check for voltage on pin 1 of the ignition module connector or at the ballast resistor. No voltage there would indicate either a problem at the bulkhead disconnect or a bad ignition switch. Remember that just because some parts are new doesn't mean that they can't be defective. The regulator and alternator have little to do with this unless they are supplying to much voltage and are overheating something and if it were the battery, the whole vehicle would be dead.
--
If at first you don't succeed, you're not cut out for skydiving



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Check the system according to the FSM. You don't say how you checked the box or resister, but simply checking the connections isn't enough.
The only way to trouble shoot this system is by using the diagnositcs found in the FSM. What you don't say you covered was the pickup coil, possible loss of ground to the orange box, or loss of ground to the engine block. The ballast resistor could be a problem, if it opened both sides, since one starts the truck, and one runs it.
If you need details on the factory diagnostics, email me, or post here.
--
Max

"Everyone is entitled to his own opinion, he is not entitled to his own
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Max and TBone, thanks for the input!
Tbone, I checked the ballast resistor, ECU (orange box) and voltage regulator with a multimeter and they were within the ranges in my Haynes manual. I cleaned all of the connections as I inspected, and other than some dirt on the outsides, they were all clean and non- corroded. The battery connections are clean. Everything around the coil was checked for wear/corrosion/improper contacts and cleaned. I don't think it's affected by heat as it's shut off within less than a minute of starting. The smoke off the neg terminal I think you are right in that it's heat from the resistance of cranking.
Max actually pointed out something I overlooked and that was the pick- up coil. I'm smacking my forehead for not including that when I checked out the distributor. I also found another guy with exactly the same problem and symptoms with his 360 and the pick-up coil was his problem. Here's to hoping it's mine as well.
I'll get back when I check it out.
BTW- his page, which other people may find useful, is here: http://www.retroaudiolab.com/dodgevan.htm look for the 6/24/06 and 6/25/06 entries.
R(k)
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On Aug 28, 7:24?pm,

Pickup coil in the distributor. When you pull the distributor to change it and before removing the coil check for continuity while wiggling or flexing the wires.
Bob AZ
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Here is another thought, JUST A THOUGHT.
We had a 1997 Jeep Cherokee that would die for no reason what so ever. By time I would get to where my wife broke down it would fire up and run fine. It turned out to be the ignition coil. The same thing happen several time some years later, turned out to be ignition coil. We now have a 1996 Dodge Van. My wife called and said "It just quit". On my way to get her, I ran by the parts store and picked up a coil. Got to her, it fired right up. I changed the coil anyway, no more problems with it dieing out of the blue.
Fred
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Fred wrote:

Ignition coils are sensitive to heat -- the resistance of the wire inside increases with temperature. So, where did/do car manufacturers mount the coils? On the engine -- the *hottest* part in the engine bay! Bryan
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wrote:

positive battery cable that ran from the battery to the starter. It was corroded inside, but you couldn't tell by looking at it.
--
------MoParMaN------

TEDWARD Said:
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Well, it has turned out not to be the pick-up coils- I replaced the entire distributor (it was 5 bucks cheaper than the pick-up coil plate!) and it died again in the same way.
I've gone through the harness coming from the firewall this morning and just finished re-wrapping the second smaller harness tonight (with all the upper engine connections like the coil, alt, pick-up leads, etc) and found no breaks, burns or chaffing on any of it. I'm convinced it's not a problem in the wiring itself and am leaning towards a component.
The starter relay checks out fine, as does the ballast resistor. Going to check the coil tomorrow.
Thanks for the leads, everyone.
R(k)
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snipped-for-privacy@gmail.com wrote:

You didn't mention checking the ignition switch. T-Bone pointed that out in the first reply to your post.
--
Ken



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Fixed! Problem turned out to be the ECU. Even though I had previously checked it, that test only checked for ground on pin 5 which was the only test I could find until another member (Max, thanks!) told me of another way to test it.
The only lesson I can impart here is to make sure you're testing the right thing the right way. I know it sounds like a "duh" thing, but overlooking something or not knowing about it can lead you to buying parts and going through trouble you don't need.
Thanks to everyone who had input and advice! See you on the road.
R(k)
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