I have this code on my 2000 silverado. It comes back as fuel pressure sensor but I replaced it already. Originally a scan tool wouldnt erase the code. Then the code went out and came back after a few drive cycles. I was able to erase the code this time with a scan tool but it did come back again.

What should I do now?

 

Check the wires to the sensor, you should have a 5 volt reference wire and a ground wire plus a signal wire. use a DMM and back probe the wires with the key on engine off. If you don't get any voltage then you have to check for a bad ground wire.