If it is the same problem my daughter had, it didn't matter how many times we dried out the moisture. Every time the engine was started again, more water was forced out through the leaking core plug.
In the end it was repaired using a liquid metal filler. That worked until the car was sold a few months later. I don't know about how long after that.
Still, try your compression test if you think it is low on compression on that cylinder. But if it isn't, remember what I told you.
ChicksFan
November 2011