CPS, fuel pump, or ?

I have a 91 Laredo, 4L, 4×4, AW4. Starts and drives fine for 10 to 15 minutes then just shuts off. No surge, no sputter, nothing, all of a sudden your just coasting. If it sits for ~ 20 minutes or so, it will restart and repeat. Searching the interwebs led me to believe it was the cps. Replaced it and exact same symptoms. Fuel pressure is 36 psi and goes to 44 with the regulator vacuum line disconnected. Not sure where to look next.

Check the ignition coil....
Sounds as thought when the block warms up; the coil windings get an open.

I chased a problem like yours for months with my Trans Am ('90 TPI). It wound up being one bad injector that would short out when warm and just simply kill the rest of the injectors at the same time. I believe that was a batch fire system, and I don't know if the XJs used batch fire or not. Just throwing it out there as one detail to consider. I found it by discovering that the engine would run with that one injector disconnected.

A new coil seems to have fixed it. Thank you.