This was really weird, but my O/D light came on all of a sudden while I was driving and then I pretty much had to put the gas pedal to the floor to get it to move past 60. I don't know if it is the sensor or what the problem is, but any help will be appreciated!!

 

The flashing O/D OFF light means that a transmission trouble code is stored in the PCM. You will just be guessing until you get the code pulled.