What Is wrong with my car any idea rotary engine mazda rx7 1991?

[Yvette Dynamic]

i turn on the car in order for it to stay on i have to hold the gas in it will not idle & if i let the gas go its will just kind of shake then shut off

here is a video of what it is doing

http://www.youtube.com/watch?v=d2j3nehpz7k