[91redgt]

I have a 91 gt with an aod trans. When manually shifting the car from 1st to 2nd with full throttle, it will not shift until I let off of the gas. When I dont have it at full throttle, it shifts fine. Also, when it is in drive, it shifts fine if it is at full throttle. Someone told me I would have to get my trans rebuilt b/c it was slippin, but then i called up Performance Automatic in Md and they told me it could be my Throttle Valve (TV) pressure cable. I am wondering what it is and trying to figure it out online before I have to take it to a shop. I really don't want to pay 1 grand or more to get it rebuilt. Also, a person I know has a 5 speed that is rebuilt, and I was wondering is it hard to switch it over from auto to manually and how much money is involved? Thanks