DTC P0451 EVAP. Emission System-Pressure Sensor Range / Performance: General Description

The Fuel Tank Pressure Sensor (FTPS) converts fuel tank pressure to a proportional analog voltage signal which is read by the engine controller for evaluation during execution of the Evaporative System Diagnostic. The Tank Pressure may be below atmospheric pressure (ie. a vacuum) or above atmospheric pressure.

The fuel tank pressure is used to measure the difference between the air pressure (or vacuum) in the fuel tank and the ambient air pressure. The Powertrain Control Module (PCM) supplies a 5-volt reference and a ground to the sensor, which allows the sensor' s output voltage to range from 0.1 to 4.9 volts.