transmission will not engage on 1995 Ford Contour

my car ran perfect the day before about 150 miles. the next day I headed to town,about 1.5 mi, after about a mile the trans disengaged and was just rolling, after a few blocks i turned and it engaged,so i went around the block and then it did it again. this was at my sons house, and we checked the fluid, it was clean did't smell burnt but was overfull. i left there to go home, it would engage for a few seconds then let go. after about eight tries i made it home. what could be the problem?

Asked by for the 1995 Ford Contour
MLP switch...cost bout 150 to get it repaired. Its on the bottom of the transmission, if it is automatic that is, and it is the part that does the "gear changing" for an automatic. It will go into what is called "Limp Home" mode and go in and out of gear.