Blowing foam particles

My 2000 Golf recently started blowing particles of plastic foam out of the heater/defroster vents. A rattle has also developed under the dash which seems to be related to the road surfaces. I assume some component in the heater/AC system is disintegrating; does anyone have any experience in locating and repairing this problem?

m-i-c, k-e-y, m-o-u-s-e…

Some vent system doors have this foam attached to them so the doors don’t make any noise hitting openings when the mode is changed. This foam is also used between plenums in vent systems to seal the system from leaks. This foam can deteriorate where starts coming apart and is ejected out of the vent system. Not much can be done when this starts happening. Unless you want to completely remove and disassemble vent system to remove the old foam and glue on new foam to the vent system components.


The blower is chewing on something. Gain access to the inlet side of the blower and take its toy away.

I agree with Tester–it is the foam surrounds on the dampers in the air ducts.