over the summer i had water all over my trunk and on the floor of the back of my car. its most likely your tail light gaskets. just replace em or make new ones yourself. thats the most common problem with water in the back of the car in second gen integras. if that doesnt work, just clear out the moonroof drains by blowing air through the a frame in the top of the car. dont poke it with anything though, unless you want water commign out from the side columns