I'm not 100% sure for a 2004 but on a 2002 it in on top of the fuel tank and can be accessed, without removing the tank, from over the frame rail. If you have a code P1450 it is very possible that it can be your problem.
fuel pressure sensor is located on the tank
On a 2004 Ford F150, the vehicle speed sensor is located on the driveshaft of the transmission. Some models of 2004 Ford F150s use an ABS sensor instead of a vehicle speed sensor.
The barometric pressure sensor is located on the left side by the carborater, it has 2 vacume lines and a electric connetion.
Very carefully!
where is the crankshaft position sensor a bank 1 circuit malfunction on a 2003 f150 at
on the top of the differential
The 1997 Ford F150 4.6 liter engine throttle position sensor is located on the top of the transmission. The sensor will be connected to the fuel injection rail.
The vehicle speed sensor is on the transmission. The ABS speed sensor is on the differential.
The sensor is located in the sensor assembly. It is inside of the transmission, the pan will have to be dropped to gain access.
its located at the rear drive axle
forward of the firewall
Speed Sensor The sensor is located on the rear axle housing.