It was the ventilation hose on the connecting manifold behind the idle valve.
I have to say that a chewing gum after 3 days of use has a firmer consistency than this hose.
Pictures in the appendix.
Dissolve the 6 screws of the manifold, remove the part and remove the causer.
Setting up the new tube went better with some glycerol than I expected.
==References====External links== It took 40 minutes.
Have a good weekend to all of you.
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There is actually nothing to see on a twisted hose
