Where is the fuel tank pressure sensor located on 08 Suburban?

Answer 1

It is located on top of the fuel pump module. You will find two electrical connections on top of the fuel pump module. One connection has four wires and the other has three wires. The one that has three wires is connected to the fuel tank pressure sensor. This sensor monitors the negative pressure in the tank during the EVAP self test mode. This sensor can be replaced without removing the tank or the module if you have nibble fingers. First purchase the new sensor and you will see how it is held in place. After disconnecting the electrical connection and spraying the area with a little lube the sensor will wiggle up and out. Recommend cleaning the area with compressed air first to avoid letting any dirt get inside the tank.