The Fuel Tank Pressure (FTP) sensor measures the difference between the pressure or vacuum in the fuel tank and outside air pressure. The control module provides a 5V reference and a ground to the FTP sensor. The FTP sensor provides a signal voltage back to the control module that can vary between 0.1-4.9 volts. As FTP increases, FTP sensor voltage decreases, high pressure equal low voltage. As FTP decreases, FTP voltage increases, low pressure or vacuum equal high voltage.
Removal & Installation
- Disconnect the negative battery cable.
- Remove the fuel tank.
- Disconnect the fuel tank pressure harness connector.
Remove the Fuel Tank Pressure (FTP) sensor.
- Install the new FTP seal.
- Install the fuel tank pressure sensor.
- Connect the fuel tank sensor harness connector.
- Install the fuel tank.
- Connect the negative battery cable.
- Inspect the EVAP vent system for a restriction.
- Test the low reference circuit of the FTP sensor for an open or for high resistance.
- With the GE-41415-50, connect the J-41413-200 to the fuel filler neck.
- Start the engine.
- Allow the engine to idle.
- Use the Purge/Seal function to seal the system with a scan tool.
- Command the EVAP canister purge solenoid valve to 20 percent.
- Observe the vacuum/pressure gage on the J-41413-200 and the FTP parameter on the scan tool.
- Allow the vacuum to increase on the gage of the J-41413-200 until it reaches approximately 16 inches H2O, or until the vacuum reached the abort limit on the scan tool.
- If the difference between the FTP parameter on a scan tool and the vacuum/pressure gage on the J-41413-200 was more than 1 inch, replace the FTP sensor.
- If the maximum Fuel Tank Pressure Sensor parameter on a scan tool display was less than 3.2 volts, replace the FTP sensor.