I am making this thread becuase I have seen in many forums people complaining about black felt or soft foam blowing out of their vents (Mostly in summer with AC working).
We have found the culprate and have also attached a photo. It appears that the center vent flap/door is coated with soft plastic foam in order to seal when it closes. Over time I guess this material begins to decompose and fall apart. The result is black soft plastic felt being ejected under high air blower speeds.
I am unsure if this item is offered still by Mercedes-Benz. Mine personally is not blowing chunks so I have not yet had to make a repair. I would imagine that if this was the case while the dash was off someone could save themselfs embarassment by using some sort of high quality ducking material to re-do the seal.
Indeed this is the foam that chunks off and blows through the vents. It can be replaced when taking apart the system with new foam that will last another 15-20 years before degrading. This is a good job to do at the same time that the ACC vacuum pods are replaced. This job requires removing the dashboard and center console.
