To remove excessive moisture in the car, you can try silica gel
This product works well.
Amazon has silica gel by the gallon too!
Word of caution...
Be sure the container you have it in can hole a lot of water.
We had placed a damprid like product on a hardwood floor in a house we owned.
It was behind a piece of furniture and we forgot about it
Needless to say it pulled water from the air till it overflowed. Left a nice big water stain on the hardwood.