Power loss and hissing noise when revving

[XIBRAX]

hiya people, I have a mercedes c220 cdi 51 reg, and recently I am getting a power loss when accelerating I get a really bad hissing noise its sound like the heating is on full pelt but no air is coming from the vents! when I got a previous problem fixed from a mechanic, I was told that the intercooler pipe will need replacing soon which is why its making a hissing noise, could this problem be cause of the pipe? many thanx Ibrar

 

[whitenemesis]

Yup! The intercooler pipe went on my car just recently.

Symptoms just as you describe