I'm in rainy Seattle. Windows fog up super quick on the G1 I just purchased here in early winter (45-50F rainy outside). No evidence of any water leaking into interior. New cabin air filter. Also have a G2 and G3, neither fog up super fast. I usually like to run AC least as possible to allow ICE to shutdown more. So I set air flow from outside (not recirc) fan on 1st setting. Temp on 70+ Thought I ask before going over the car to look for any water entry.
I have noticed keeping the interior glass clean is a constant struggle. I've long suspected the interior out-gasses and condenses something on the glass. So in the Fall, I do a through cleaning knowing it is only good until late winter. GOOD LUCK! Bob Wilson
Yes, I windexed it 2X and the G1 glass seems to have more of a film on it. Perhaps you are right about the interior. I guess it is AC on more then
One year I tried a Rain-X product for glass fog. It worked by consolidating the fog droplets into drops that ran down the glass. Not a bad product but I've had no interest in repeating. Try it on the passenger side first, side window. Bob Wilson
I just spent 4 hours going through Seattle/Bellevue this morning... it was a tough day to be on the freeway. I've found here in the PNW that this time of year the windows will fog easily until the Prius has warmed up. I'm not a real fan of cleaning the inside of the windshield, but it's got to be done. I've used Aquapel glass treatment and I like it better than RainX. However, I don't use anything on the inside of the windshield. Some of these moisture repellents can be difficult to clean and re-apply.
