I ended up taking it back to the tranny shop and told them to fix the problem since the moisture issue was explained up front. He said he replaced the TSS again for the 3rd time, and now it seems to run fine. I ran it through a car wash and drove it on a rainy day, and all seems to run fine. He said he replaced it 2 times before and it would burn out. I can't understand how 2 of 3 TSS's would be bad. Maybe he did something different and isn't telling me.
I turned the wheels hard to the left and got down under the car to inspect the TSS. I see fraying on the wires leading to the harness. I would think that it would short out, but it's not. My first instinct would be to replace it, but I don't want to touch it at this point. Any suggestions?