1995 Mustang 5.0L car has worked fine for 2 season suddenly it started to surge only on cold start after sitting over night. it only surged a few hundred rpm for a minute or 2 ...its progressively gotten worst to the point where it will stall if i dont give it gas for a minute or 2.

once the car warms up it idles fine. any suggestions?

Car has Underdrive pullies and CAI but hasnt had issue with them before.