97 Grand Prix 4t65-e transmission problem

I have a 97 grand prix gtp with a 4t65-e transmission. It started acting up and I had a computer diagnostic test ran. It said the torque converter lock up selonoid circuit was stuck open. I replaced both shift selonoids and it shifted smoother than ever before, but there was one problem. It will only shift out of 2nd gear at about 3200 rpm. Occasionally it seems to be sticking in 2nd. Any suggestions on what to try next. Also I had the diagnostics run again with no codes found.
Thanks for any suggestions you could give me. Man I was really hoping for a little more input on this problem. I got some really good info from trannyman that I'm going to work on next week. That would be caused by a vacuum leak on older transmissions, but I don't know about the newer electronic units. Well I just noticed something weird this morning. I went out to start my grand prix and the battery was dead. I removed the negative battery cable and charged the battery for several hours. After I disconnected the charger and started the car I drove it for about five miles. The transmisssion shifted perfectly at the right shift points. I shut it off and went in a store and when I came out and started it back up and drove it again it was staying in 2nd gear until about 3000 rpm again.
I am pretty sure that when I disconnected the battery it reset the computer. Anyone have any suggestions. Thanks un less its a deep cycle battery you will need to get a new one; any time in which a batter has less charge then 30% its not rechargable....

if the battery is dead have your alt checked ect... but you could have a short somewhere in your comp sys or somthing a short would cause a number of probs and kill the battery too...

if you had a mechanic do the work originally they should recheck everything they have done with out charging you more... mebbe they will even give you a new battery if its no longer keeping a decent charge.... The battery is about 6 months old and I think I accidentally left the key on overnight. The transmission is what I am concerned aboutthe most. Thanks for the info. Well I would have never believed it but my transmission problems all came down to a bad spark plug. It had a slight miss but that was all it took. The computer tells the tranny to shiht based on the rpms and the vehicle speed. If there is a conflict between the two it throws the computer out of whack.
Thanks for all of the help, and thank God it was just the spark plug.Car Repair Talk's forum.