Audi 5000 turbo power loss when Engine Hot

Hello, I recently had some problems with my engine not starting when it was too cold or over 100 degress C. i had that fixed and they apparantly replaced 3 air hoses including the big hose from the intercooler to the intake manifold which had a huge rip in it. when it would get started before they fixed the hoses it seemed to have a decent amount of power and thats what i was used to.

But i noticed that after they "fixed it" when the engine started to warm up above about 80 degress C it would completely have no power. its fine when the engine is just started but once it warms up it seems to have less power then my moped.

I noticed that my air filter that i bought a couple months ago has blackish oily liquid stuff in the bottom.
i'm sorta lost to how this fuel/air system works but it seems like the more air that it lets in the fuel is automatically let in because of a lever that pushes up or something in the air box. but im not sure exacty how this works or if i'm right. but it seems like fuel is leaking down from the top of the air box down to the very bottom. if it helps to know that.

Anyone have any idea on what could be causing this power loss?