overdrive is not working the way it should
when I am driving between 40 and 50mph it works fine but when over 50mph when you give the car gas it keeps kicking out of overdrive until the computer goes into default mod then it works fine
It might pay to get a code reader on it & let us know what it tells you. Sounds like the transmission control computer is giving problems. Open it up & have a look for the obvious capacitor leakage problem with this one. These computers have a history of SMD chip resistors going open circuit, which is impossible to spot, but easy to measure with a multimeter. I've personally repaired hundreds of similar systems over the years.