JoeO

Can anyone tell me what this broken hose is/was servicing? ...before I take the car to a technician.

I was examining my engine bay today and happened to notice this hose was broken in two (my fingers are holding one end). The car has some minor issues but is drivable and gets me from point A to B daily, but that hose could have been broken for days, months, maybe years. I'm not sure.

I have a 2003 Audi A4 3.O 6-cyl CVT.

john_gonzo

That hose services the two vacuum motors at the front of the intake manifold. In your pic, those motors are the bulb-like things – one behind your finger, the other at the end of the short vacuum line on the left.

These are activated when engine speed is about 4200 rpm and above. In other words, the broken hose is not a problem until the engine reaches those speeds. The two arms coming out of the vacuum motors work together to rotate a part inside the intake manifold. This changes the path for the incoming air from a long tract to a short tract.

Anyway, all three of those hoses should be replaced (the one in your fingers, and both hoses on the green tee).