At the beginning of this article, we want to review the cons and pros of monitoring fuel levels using the standard, built-in fuel level sensor:
Advantages:
The built-in sensor is present in every vehicle.
No additional costs for installing monitoring equipment (additional fuel level sensors).
Disadvantages:
Inaccurate measurements and susceptibility to external influences: Built-in fuel level sensors do not always provide accurate readings due to various factors such as the shape of the tank, the position of the vehicle (tilt), vibrations, and the design of the float. This can lead to significant errors, especially during sharp maneuvers or driving on rough roads.
Delay in data updates: Many built-in sensors have inertia, leading to delays in updating fuel level readings. This is particularly noticeable during sharp accelerations, braking, or stops when the fuel level in the tank changes quickly.
Built-in sensors often have significant errors at minimum and maximum fuel levels (so-called "dead zones"). In the TT2 system, this appears as data "freezing" at minimum/maximum fuel levels.
One built-in fuel sensor for two tanks: The built-in fuel sensor is always installed in the larger (primary) tank (if the vehicle has two fuel tanks). In such a configuration, the smaller tank can be used by the driver for fuel manipulations ("blind spot" for fuel monitoring).
For more accurate fuel level measurement, it is recommended to consider using additional systems, specifically the installation of additional fuel level sensors in each vehicle tank.
Recommended settings for the fuel module for a single-tank vehicle (tank volume not exceeding 900 liters):
For a dual-tank vehicle, fuel filtration needs to be increased, for example, to 60 liters (the recommended and allowable fuel fluctuation is 5% of the total volume of both tanks). This rule can be applied only if both tanks are connected as communicating vessels. If the fuel does not flow between the tanks by gravity but uses an electromechanical pump (e.g., DAF 105,106 vehicles up to 2017), it is recommended to set the volume of the larger (main) tank in the system.
Other values for time/speed can be adjusted after the vehicle has been in motion (both increased and decreased). Often, the changes made will be due to the cons described at the beginning of the article.