Short story:
Fuel too lean code, cleared, let car idle for a minute, drove terrible, scanned for codes, heard hissing sound under hood.

The hose: Huge slit in it. If I squeeze the hose it's about 25% missing but otherwise collapsed

Any idea what hose it is?




Ty in advance!

 

That hose right there is one of the PCV system hoses I believe.

You can either replace it with the factory part, or you can get creative and find a reliable and preferably threaded silicon pipe of the same diameter.

 

Also looks like your cylinder head coolant flange and/or expansion tank is leaking. That's what all that white crusty stuff is on pretty much everything in that picture.