1998 Ford Contour 2.5 LX hesitating and bucking

Hello I just receintly purchased a 1998 contour lx 2.5 v6 with auto transmission and for the first couple of days it drove perfect and then when I was driving on the highway it felt like the car had died, then the front end bucked like 2 or 3 times then it went right back into gear and off I went it has done this every time I start the car up and started driving at low speeds city driving or at high speeds highway driving, it does it if there is a full tank of gas or almost on empty, I have been reading up on this issue and it seems like there is no clear answer on how to fix the issue and I really don't want to dump a bunch of money into the car and thoughts on this issue would be greatly appreciated.
Thanks :D