1997 5.2 cuts off while idle

Hello all! New here. Recent owner of my fathers truck a 1997 Dodge Ram 1500 5.2 4wd. I am trying to get the old girl back to form. The truck currently has 200k miles and runs great.

However I feel like I have been chasing a gremlin. The truck will cut off while idling after a few minutes. Just like the ignitition was cut off . No codes.

So far I have replaced the coils, plug wires, plugs, crankshaft position sensor, idle air control.

I am at a loss. The truck runs so good it makes no sense that it just cuts off.

My ideas?

Throttle positioning sensor maybe? I think on these that the truck would throw a code so it mostly isn't but generally when they go bad their is a sudden power loss when accellerating and can stall out and then sometimes not start. I know back in high school I had a 1997 half ton 4x4 that had a camshaft positioning sensor go bad and at first it would die after idling for a minute or 2 then it wouldn't even start. That was a fun experience trying to track a new one down too because the dealer said these trucks didn't come with one, and every part store called it a different name than the others. I think I have read on Google searches in the last few years people have had similar issues where the the check engine light throws the code for it and the dealer says that's weird because they didn't come with that sensor. I think when mine first started failing the check engine light didn't come on.

Check for codes by turning the key on and off 3 times as well, on occasion it will show codes not known by scan tool.

Try replacing the O2 sensors as well. May not be the exact problem but it sounds like it could be related.