Intensive Washer Solution
I am using Porsche Special Silicone Remover (928.628.931.00) in the intensive washer reservoir and find it cleaning effectively and not doing any (visible) harm to paint or rubber - in contrast to other silicone removers.
It does, however, partially dissolve the wax on the roof, where the washer fluid is drawn during driving. This causes some streaks in the wax coat to develop over time, but if you re-wax the car, the streaks are gone again.
Another tip: If you store your car during the winter, you might want to seal the container with a thin plastic foil or something, as the fluid tends to evaporate through the vent holes in the cap of the container. This way I "consumed" three bottles during three winters. But don't forget to unseal it ...
90 S4 A/T Euro
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