DeVille V8-4.6L VIN Y (1998)
Powertrain Control Module: Description and Operation
EVAP Fuel Tank Pressure Sensor
DESCRIPTION
The EVAP Fuel Tank Pressure Sensor is mounted to the Modular Fuel Sender assembly.
OPERATION
The EVAP Pressure sensor is a sensor that changes resistance based upon fuel tank pressure (or vacuum). A vacuum is considered negative pressure.
The PCM provides a 5 volt reference and ground. The EVAP Pressure sensor signal varies between ground and 5 volts as fuel tank pressure varies. As
pressure decreases (negative pressure, or vacuum), voltage increases. As pressure increases, voltage decreases (positive pressure, low voltage). The PCM
uses the EVAP Pressure sensor values as an indicator of EVAP system efficiency.
