Car won't keep running in park

I have a 95 T-bird 4.6 I can start the car but I have to feather the gas pedal to keep it running. Also in gear it just dies. Help!! There are no fault codes that come up.

Isolate small things first, like vacuum leaks and unplugged sensors, air filter, change the oil, check fuel pressure at the rails to diagnose a fuel system problem... When was the last time you changed PM stuff like fuel filter? Last tune up?

Idle Air Control (IAC) Valve