1998 Ford Escort ZX2 Hot. Cant hold stay in idle then stalls.

I'm thinking about buying a 1998 Ford Escort ZX2 Hot Sport Package coupe with everything perfect...except for the engine. The car starts like a charm...but then it stalls unless you keep your foot on the accelerator pedal. So it goes like this
1.)Keys in ignition
2.) Starts
3.)Revs to 3,300 RPM then dies.
My way of keeping it going
1.)Keys in ignition
2.)Starts
3.)Revs to 3,300 RPM and keep foot on accelerator pedal to keep running.

To kill the car just take your foot off the accelerator pedal and it stalls