I wouldn't panic, swirl flap getting into cylinder happens with plastic manifolds but still is quite rare - there were a few cases mentioned on polish Alfa forum over years, and so there is generic advice there to sort that out. Though, since you said you cleaned swirl flaps, you probably very highly minimized probability of such problem at lest for another 50kkm or something, even if you didn't blank EGR. If you want to leave swirl flaps and do a lot of km option worth to consider is to blank EGR - at least in Poland you can buy ready blanking piece/pad (not sure how to call that), if not where you live you can do such yourself from metal sheet (thin stainless steel I guess). If you blank it physically, somebody who is capable of doing ECU reprogramming must disable EGR from ECU (not sure how much is that where you live, in Poland I payed like EUR25 extra on top of ECU tunning/mod I did in the same time), otherwise immediately check-engine light will pop up. If you blank EGR then you at least stop the dirt back collecting inside intake manifold, so swirl flaps should be happy.
Removing EGR disadvantage is that engine warms up bit longer, but advantage is that EGR won't ever be an issue (again blocking itself earlier or later).
Alternative is to leave EGR, but remove swirl flaps or change to alu manifold with these removed and holes welded. E.g. the same engine in Fiat Stilo (140BHP) does not have swirl flaps, probably similar case with 156 and other FCA cars manufactured just before 159, not sure though if intake is compatible, or if you need to consider only updated of one from 159.
thank you very much for your detailed response. i am planning to blank egr and ecu programming . meanwhile, if all swirflaps are their hole-finger crossing- , have cleaned them to service.
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