1997 Stratus

I am looking a buying a 97 stratus with mechanical issues. The owner says the car starts and runs fine but as soon as you put it in gear it sputters and dies. He thinks it is electrical and not mechanical problem with the trans. Any ideas what i am getting into?

Nevermind the car was a piece of junk. I am not interested.

I have a 1997 stratus. I want to put a new engine in it and change the transmission to manual