My 99 E320 has a 9" vacumm hose coming out of the top right rear of the engine that is not connected to anything. I stuck a golf tee in it for now. Where is it supposed to go? Pic attached.

 

there should be a white/clear plactic hose coming out from the fire wall almost where you have the golf tee sticking out of the hose. look behind that wire harness, those hoses do pop off occasionally. and i believe that vacuum hose attaches to the back of the engine correct?

 

I only got one reply but it was all I needed! Thanks, that was it. Do you know what that hose is for? I haven't noticed a difference in drivability.

 

i believe possibly the ac blend flaps, or something for the climate control unit.