Crackers/Rassels in the engine compartment during gas removal

Hello dear ones, I have recently had a Fiat Uno 92 1.1 with 50 hp, which previously belonged to an 82-year-old grandpa, who has driven with him for a maximum of 2,000 km/year in the last years. But for that the Uno tip-top is in the shot, if you don’t mind that he smashed both sides, because he probably didn’t see it right anymore + went somewhere along. But now to my problem: with a warm engine starting from about 80 km/h, as soon as I take the gas away, in the front of the engine compartment a clapping is in the This sound can sometimes be heard even at slower speeds, but this time strangely when I speed up. What can that be? Is it something you can ignore or is it something worse (storage damage?)? lg from Dani P.S.: He has the well-known Fire engine from Fiat.