Fuel Tank Pressure Sensor: Description and Operation

Fuel Tank Pressure Sensor:

The fuel tank pressure (FTP) sensor measures the difference between the pressure or vacuum in the fuel tank and outside air pressure. The FTP sensor mounts in the top of the fuel tank-sending unit. The PCM provides a 5-volt reference and a ground to the FTP sensor. The FTP sensor provides a signal voltage back to the PCM that can vary between 0.1-4.9 volts. As the FTP increases, FTP sensor voltage decreases, high pressure = low voltage. As the FTP decreases, FTP voltage increases, low pressure or vacuum = high voltage.