Heater core "doors " melted from the R type antifreeze breaking down to an acid. This cause the heatercore to break, antifreeze entered the car through the vents and also oddly enough filled the gauge cluster with steam fogging the cluster. It's $800 for a replacement so I bought a fitting and some hose clamps and bypasses the heater core so I could still operate the vehicle when it wasn't too cold. However when operating the vehicle in cold weather all the windows had to be down due to your body heat causing all glass in the vehicle to fog. Replaced the heater core in January, flushed the radiator and installed regular type 50/50 antifreeze and not the VW R-type fluid to prevent break down into acid again.

- Washington Crossing, PA, USA

Windows fog up very easily with an unusual amount of moisture with minimal driving and sub normal engine coolant temperatures (when the car is "cold"). fogging forces driver to pull to the side of the road ot defog windows. Front passenger window regulator unit failed on highway causing window to roll down on its own and stay down. Owner forced to disconnect motor until problem could be diagnosed. Window regulator/motor replaced. Driver's window produced a clicking sound upon reaching the closed position. Window regulator replaced.

- Portland, OR, USA