1991 Grand Am Torque Converter stays locked up when warmed up...Any suggestions?

[BDK]

1991 Pontiac Grand AM 2.5L
My '91 Grand Am has a 3 speed automatic transmission with overdrive. The overdrive kicks in above 45 or 50 mph automatically. When traveling in overdrive for a long period (1/2 hour or greater), the transmission will not shift out of overdrive when slowing down or coming to a stop and the car stalls. Upon restarting the car, (in neutral or park) the transmission is still in overdrive. It will work again once I turn off the car and let it cool down. Do you have any idea what might be causing this? I would like to figure out if it is a bad torque converter or something in the valve body in the transmission.
I have dropped the pan, cleaned and put new fluid in and has not helped.
Any help would be wonderful....

 

[Unregistered]

My 94 Cheve Cav did the same thing. Read somewhere that the selinoid on the torque converter sticks when it heats up, they fixed it at transmission place.
Now not problems.

 

[Unregistered]

You may have a sticking lockup solinoid in your transmission. I don't know about these cars, but on my Buick it was easy to get to with the pan removed. two bolts and a connector. Not expensive either. Did you notice any wires inside when you had the pan off? If so, that should be it.