Hello,
Thank you for specifying the information.
You should create data sources in TAVL server management. You should be using calibrated values from fuel sensor to set up this parameter correctly. After getting the calibration data, you should be able to set up the data source by yourself following the guide for fuel sensor configuration in TAVL server:

If you have not done calibration and no a1, a2, a3, a4 values are calculated please inform us we could prepare you a full guide.
If you encounter any issues to set up you LLS sensor data, please feel free to contact us, we will be happy to help.
Regards.