quick update: yesterday they called me saying that, after having carried out all the tests, it seems that the problem is dirt in the system that may ruin the components (entered at the factory? At the time of replacing the faulty pump? Because of the faulty pump? who knows ...) so at 3.27pm yesterday they received the email with the authorization to replace the entire system: steering gear, pipes and the pump again (I wonder why not the tank too) as the dirt may be everywhere or moving from one point to the other . This morning they will proceed to order the necessary parts and we will see, fingers crossed for a definitive resolution