Partially the problem is solved, just deleted the fuel_cons.ini file for each car, now AI always starts with a full tank of fuel, moreover, in qualifying AI no longer ignores the base fuel value specified in the car.ini file, before that AI used a random fuel value in qualifying, most often it was almost a full tank, which quite illogical.
And so, the problem is almost solved, almost, because still some cars on some tracks ignore my requirements, for example:
Mercedes C9 on the Lemans SX track without chicanes always starts qualifying with 86 liters of fuel, although 50 liters are indicated in the car.ini. At the same time, on the same track with chicanes, the same car starts qualifying with 50 liters of fuel, as it should. A similar with some other cars. That is, the starting amount of fuel also depends on the specific track and its version.
What settings file is also related to the base fuel value on a particular car and track?
Thank you.