Hello Everyone, I have a big problem. My 2000 A4 1.8t is leaking coolant like it is it's job. Already gone through half of a bottle of coolant. However, I did find out where it is leaking from. I had just enough room to stick my hand in there and feel the coolant dripping from a connection piece. The spot it is leaking from is toward the back, drivers side of the engine, right in front of the fire wall. It appears that the hose that is connecting at the spot of the leak is possibly going to the heater core, but I can't really see where the hose is going. It appears that it is some sort of plastic connection piece that is connecting to a metal hose.

I took a picture as best as I could and I circled in green where the leak is coming from. Could someone please tell me what part it is that I need so I can change it out and stop laying coolant all over the place? Thank you in advance for any help you can offer!