I recently got an error code on my 2000 Chevy express 3500 5.7L V8. The code reads that I need a new Fuel Tank Pressure Sensor. I bought the part, lowered my fuel tank just enough to where I could reach into the middle of the fuel tank to pop off the sensor. When I lowered the tank I noticed that there was not one installed, so I thought nothing of it until I went to plug it in. I do not having a 3 pin wiring harness attached to the 4pin for the fuel pump module. Its four wires that are in a harness leading to the way front of the van, connecting to an adapter, which from them there goes elsewhere. Essentially, I got the FTP sensor error, from a check engine light. Went to replace it, which sits on top of the fuel tank, on the fuel pump. I find out that for some reason there isn’t even one attached to the fuel pump, and there is no 3pin connecter to connect the FTP sensor that I’m trying to install. I have noticed pretty intense poor fuel economy as well as poor acceleration, and occasionally stalling.
Update: I am now receiving a different code, which is P0174 " solution; replace MAF "
I uploaded more here since I can only post one image