6 moths ago i had this issue and replaced the map sensor and now it happened again, so of course it i replaced it again but it did not correct the problem. I brought my 04 gand cherokee to a different mechanic per my origianl mechanics request to get a more in depth diagnostic and he said its eiher the fuel fllter-regulaoter or fuel pump. We tried the filter regulator and no success. We dont want to put the pump in because we are getting 60psi connsitantly. We also changed the the plugs because they needed to get but of course thats not the answer, Perhaps its the trottle position sensor which does go bad on occasion according to msn. Anyone got any idea? thanx