Running good, shuts off, then back on (most times)

[vlt2]

My '87 22R/5speed runs great, but while driving down the road she will just shut off, lights, radio, engine, everything and most times I can turn off the ignition switch and then back on and it comes back to life. It's been doing this for a long time. When you start it from a stand still, she either will start up as soon as you engage the ignition, and if not you may have to turn off the ignition, take the key out, and do over until it starts. Sometimes i go thru this many many times, but she eventually starts up.
I suspect there is ignition switch problems, but not being very electrically inclined, i don't know how to determine that or what the problem is. I just rebuilt the engine, tranny, and re-sealed the transfer case (she has 320k miles on her, I bought her new). She runs great now, but i think its time to correct the electrical problem i have.
Any suggestions??????

 

[SilentYoda3]

make sure your engine is grounded. I had this exact problem with my 1983 bronco, drove me crazy for the better part of a few weeks until i laid my long flathead screwdriver across just right and the problem went away. Spent about $400 in parts trying to chase the problem down that a $9 ground strap fixed :happens: Turned out my engine was grounding on my e-brake cable on the back diff. I would try to start there.

 

[RAD4Runner]

Definitely Inspect Wiring

My '87 22R/5speed runs great, but while driving down the road she will just shut off, lights, radio, engine, everything and most times I can turn off the ignition switch and then back on and it comes back to life. ...
I suspect there is ignition switch problems, ... I bought her new). She runs great now, but i think its time to correct the electrical problem i have.
Any suggestions??????

Yes, ground is one thing that's common to all those that shut off. Ignition switch's possible, too but less likely.

One thing that's easy to check and could also easily go bad is where battery negative connects to engine compartment wall here:

Metal is painted so ring terminal does not contact it directly. Ring terminal relies on making contact with bolt, which could be corroded (=poor contact):

On my 86, I sanded the paint down to bare metal, and cleaned ring terminal so it will make direct contact with panel metal.

Then, I applied carbon-loaded silicone grease to surfaces before screwing ring terminal back.

I also relocated two white wires with black stripe directly to this same point, almost directly to battery negative.

Someone on Yotatech has illustration of engine ground locations here

 

[vlt2]

Thanks for the tips, i'll check it out this weekend.
i'm thinking it is the ignition switch, since that's the only place that shuts everything off at once while it's running, lights on, a/c on, etc.
I failed to mention that i can take my key out of the ignition whether it's running or not.