Originally Posted by Mantony1983
I totally understand that, but have you ever heard of the thing that rises with the water getting stuck for no reason, no signs of problems and than gets stuck and then is fine after you jiggle with it a little bit?
It is a mechanical device subject to the imperfections of the designers and manufacturers.
You're over thinking this. Sometimes things just malfunction. Even our children.
It seems to me that you are doubtful of your son's story. Toilets can and will do the darnedest things but they cannot make you believe your son.
What story from him would you believe without a second opinion? Maybe he stopped up the bowl with paper towels. After spending too much time in the bathroom doing whatever it is that teenage boys do in the bathroom, maybe he was too embarrassed to tell you the whole truth. Maybe he had a female visitor overload the toilet with feminine items. Maybe a condom started the whole thing. Syringes catch a lot of paper and stop up toilets all the time.
No matter what it REALLY was...I think you are better off going with the screwy fill valve scenario and just move on.