So ive got about 5k miles on this jy ZJ 4.0 i noticed after the engine bay gets to operating temp. When i idle my oil pressure drops to 0 with the check gauges coming on the dash. Hooked it to my computer at work and the oil pressure sensor reads 5.0V when this is occurring. The engine doesnt idle funny or run rough and as soon as i tap the gas above idle RPM it pops up. When its relatively cold or i havnt been driving for long it never drops like that just sits where it looks like it should. Only thing i havnt done is physically check oil pressure when this is occuring but thats next on my list of diagnostic. Any thoughts or insight into this. Im hoping its just sensor failure that is heat dependent.

 

It is mostly likely the sending unit. Buy a Mopar unit. But first check the pressure with a mechanical gauge. Hook it up and drive around for awhile while you watch it.