Theory Of Operation

The Fuel Tank Pressure (FTP) Sensor provides the Powertrain Control Module (PCM) with information on vapor pressure inside the fuel tank. The FTP Sensor is a transducer that varies resistance according to changes in pressure. The PCM provides a 5-Volt supply and sensor ground. The sensor sends a feedback voltage to the PCM on the signal circuit. As the fuel tank pressure changes, the feedback voltage changes proportionally.