Have you done the basic stuff including checking grounds and unplugging electrical connections to sensors and iac then cleaning and reconnecting? Make sure you have a known good battery, check dist cap for moisture, spark plugs, all spark and coil lead inserted all the way and vacuum leaks?
If you have done the above and it persists, I feel it is an issue with the idler air control valve or the passage leading to it may be carboned up.
The iac is the round unit with wires running to it on the side of the throtle body.
If your battery is old and getting tired, it will take some revs for the voltage to alt. throw enough juice to keep the motor running and also give the battery enough juice to maintain (thus it runs after revving for a few). It's common for batteries to begin fail upon the onset of cool damp fall weather.
Have it checked, or swap out with a known good one, even if you simply use another vehicle to jump to yours when it's cold.