There appears to be a hose come loose/missing leaving a small pipe coming out of throttle. It's sucking in air causing engine to idle erratically. When I put my finger over it, engine runs normally.
My question is, what connects here (see photo)? There is no obvious sign of a missing/disconnected hose. Can I simply seal this off? I'm really confused as to how this became 'open' as my car has run smoothly for last 4 years. All of a sudden, this!!