The issue is basically the contrast difference between inside and outside the car. Currently the camera is getting the appropriate aperture for inside making outside saturated. White balance won't do anything.
I haven't look at a GoPro 3 manual but what you need to do is get it to fix it's aperture on a spot rather than a wide pattern if possible.
Essentially it's one or the other though, the apature will be either set up for inside the car or outside the car with the alternative area being to bright or too dark respectively.
The other answer is to tint your windscreen
