1997 GMC K1500. Stopped running while being driven. The fuel pump was changed, there is 58 lbs fuel pressure but will not start unless you pour gas in the throttle body. The pressure holds and does not leak off, the spider was changed 2 1/2 years ago. After the pump was changed it started, taken for a drive, shut off and it restarted. Sat overnight, would not start this morning unless primed. Any suggestions on where to look, I am thinking it is probably some kind of sensor issue?