I did notice over the first winter, that the windows would fog up in the inside. However I never went into the back of the car. I could not figure out why until the spring, when I went to clean the car. We had had a lot of rain and there was over an inch of water on the drivers rear floor and mold on the floor mats. I wondered if this is why my asthma was bothering me. I went right to the dealer and they did repairs to correct the issue, however every time it rained the car continued to leak in a different spot for over a year and half, before I believe the issue may be okay now. I will need to wait for more rain to make that determination. I am now concerned that the floor boards are going to rot out of this car due to all the water leaks that have occurred.