Toyota Repair: 93 Camry Auto Transmission, toyota dealer, auto transmission

Question
My son recently purchased a 93 Camry. The car has 168000 miles on it. It seems to run fine with the exception of an automatic transmission that will not shift into overdrive. The dash indicator light says the car is in overdrive but the engine RPM says that is not the case. Any ideas as to how and how much to fix?

Answer
Everytime I hear that someone recently purchased a vehicle and that there is now a problem it usually means that the car has a major problem and that is why they sold it. If it was bought from a used car dealer I would return it to them and have them check it and provide an explanation as to why this is, if it was a private sale I would recommend having the toyota dealer check it out, there should be some diagnostic trouble codes in the transmission computer which would indicate what the problem may be.