1996 4Runner warms up and shuts down

I have a problem with my usually perfect 1996 4Runner 6 cylinder with 227K miles. Driving the other day Check engine light came on. Took my foot off gas and it died. It will crank but not start. Got towed home. Plugged in scanner and it wouldn’t connect and light was gone. Only weird thing I noticed is with key left in on position the idle air control was making a constant ticking.
Next day no ticking from IAC no Cel. Starts right up. Gets to operating temperature and died. Just died like you turned the key off. Had different scanner running no codes.
Leaning towards the IAC I unplugged it. Started it once it cooled off. Had a code for that obviously. Runs fine gets to temp and like flipping a light switch off it goes. So I dismiss IAC as a possible cause.
I try the ECT engine coolant temp sensor. Not the one for the dash readout. I unplug it. Runs fine and gets almost up to temp and dies. Will not restart until cool. Just cranks.
So I need some ideas for more things I can unplug, hot wire, or stick a electrical meter on.

Could be the crank sensor failing when it gets hot.

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Could be the ecu itself dying. Sets a cel, then loses the code? To me that says the power supply inside the ecu has a break when hot. Engine dies, ecu forgets, repeat.

Yours could be in the distributor and called something else: signal generator, pickup coil, etc. It signals when to fire a spark plug - like points in oldtime ignition systems. They tend to fail when hot, whether in the dist or not.

The distributor is a good idea. I had the same thing with a old Nissan Hardbody. That was it. However this truck has 3 coil packs. No distributor. Crank sensor and wires look good. If I find a way maybe I can check the voltage coming from it. 2 wire setup. I really wish I had a way to check the ecm. The other thing pointing that way is the 2nd scanner now will not connect at all. Both will connect to my other vehicles

Latest is both scanners work fine as long as it’s running. Key on nope. No codes, not even on the dash. Only got it the once while driving. The IAC is back to ticking when it dies. Noticed the EFI relay was hot. Replaced it. Started quicker but still same issue and new relay is getting warm. Thinking something in that circuit. Fuel pump maybe