A fuel tank pressure sensor is a component of the evaporative (EVAP) emissions control system. The sensor detects the amount of pressure created by the air and fuel vapors inside the fuel tank. Data from the fuel tank pressure sensor is sent to the engine control module (ECM, the computer that monitors and controls engine function) where it monitors the performance of the EVAP system and detects if there is a leak present.
The fuel tank pressure sensor is sometimes confused with another device, the fuel pressure sensor. The two, however, are not the same component. The former is part of the fuel pump assembly inside the fuel tank, whereas the latter is mounted to the fuel rail on the engine that supplies fuel to the injectors and is responsible for monitoring the fuel pressure on its way to the injectors.
The fuel tank pressure sensor continuously reads the vapor pressure inside your fuel tank. It is an important component that tests the EVAP system for leaks. The ECM is looking for pressure in a certain range, and if the sensor reports that pressures are either too high or too low, the computer will respond by turning on the check engine light. Your vehicle might also fail an emissions test if the fuel tank pressure sensor is not working properly. Some vehicles also have an emissions system fault light on the dashboard that might come on. And if a technician performs a diagnostic scan of the vehicle, a trouble code relating to fuel tank pressure and the sensor (such as P0452, P0453, or P0454) will signal that the sensor is a likely culprit.
Fuel tank pressure sensor replacement can be a fairly involved repair, since the component is typically located inside the fuel tank and must be accessed from the top of the tank.
To replace the sensor, a technician will likely take the following general steps (depending on your specific vehicle make and model):
This is demo Question
This is demo Answer