2000 XJ randomly dies while driving

[jeepinwi]

After replacing a faulty fuel pump check valve, my XJ with about 114k miles developed a new problem. After driving for about 15 miles, the engine would buck under power and after 3 miles, eventualy died. After coasting to a stop, the engine would not restart until 10 minutes later. It then ran for 15 seconds, and died again. Five minutes later, it started and I was able to drive it 15 miles home. All the way home, it randomly bucked, the engine would die and restart on its own. All the guages would drop to zero when it died and worked as normal once the engine restarted. There was only a momentary check engine light when the engine restarted on its own. Any ideas what the problem may be?

Oh yeah, 4.0L, automatic, 4wd, XJ Sport.

 

[falcon556]

Did you try to pull any codes?
Could it be a CPS?

 

[jeepinwi]

I'm not sure if any codes will be present since the CEL only came on for a split second. The CPS may be the problem, but the TPS may also be a problem. Does anybody know how to do voltage or ohm testing for the TPS or CPS?