92 FJ80 ignition cutting out mystery?

[mkmachine]

I have a 92 FJ80, stock, runs fine, no other problems, but it's developed a fun issue that I'm stumped by. It started cutting out intermittently. Driving around town, running fine, typically at a stop light, or not in motion, it would just shut off as though you turned the key off. Lights still on, engine not running. Put it back into N, turn the key and starts right up and runs fine.
I swapped the ignition switch unit, the electrical part of the switch, and it didn't fix the problem.
It's intermittent. So I can drive around town for a few miles and it seems fine, then it happens again. Then it's fine again. I'm concerned about going on longer drives, I don't know what would happen if this happened at highway speeds?
The wiring to the coil is stock, and seems fine. Is there another switch somewhere that might be failing?
I'm stumped.

 

[ppc]

First thing that should be replaced are the fusible links. $15-$20 depending upon where you source them.

 

[robnicko]

check your EFI -Main relay in the engine bay.
My parents had a 91fj80- and when that relay played up it exhibited the same symptoms. Eventually theirs had to be replaced and all good since

 

[jonheld]

A bit of percussive diagnostics should reveal the issue.
As stated above, the set of 3 fusible links off the positive battery terminal are subject to vibration and can fracture over time.
On the 3FE, the EFI main relay/contacts/wiring should be inspected.

 

[mkmachine]

It looks like it was the fusible links, they were falling apart. I wish I thought of that before I took the dashboard apart, oh well.
thanks for the help !! @jonheld @ppc