FRP Sensor\Code P0193

2005 Ford Freestar 4.2L, ocassionaly when driving car will sputter I drove it with scanner plugged in and it started out with 39 psi fuel rail pressure when car sputters even the slightest it jumps to 78 psi and stays there until sputter again then back to 39 psi trouble code is P0193 FRP Sensor High Input does this mean FRP Sensor is bad? No fuel in vaccum line!