Ford: 1996 Ford Taurus LX Tranny, ford taurus lx, forward gears

Question
I just purchased this car for 1200. Being a high school student i thought this was a steal as it only has 92000 miles and seemed to run perfect. The guy delivered it to my house and when it got here the problems started. This car when it starts to warm up maby 1/4 up the way on the dial the transmission starts slipping and sometimes may even not work at all except reverse. This is an automatic. The thing is it will run fine while it is still cold. My dad says it is something electrical and its probably just a cheap 50 dollar sensor that needs to replaced. I cant afford to take a gamble and find out i need a new whole transmission i would not be able to afford it. Is it possible it could just be a sensor causeing the forward gears not to work properly?

Answer
Keven this is one of those things were it hard to diag. with out test equp. but it could be the MAF sensor these will cause trans. to not shift but like i said with out doind a trans pressuer test it is hard to diag. if you can make it to an auto zone have then ck for codes .if the teans is slilping then you should have them and let me know..