Runs rough only when cold

[Tamerlane]

Ok, I have a 1990 Dodge daytona, v6 automatic.

When I first start it when it is cold after going out of closed loop mode the car starts running rough. It kind of misses every now and then and the RPM is around 550, sometimes it will stall. But after driving it down the road for about 1 minute it runs fine?

Is it possible that I have to reset the computer.

I have a brand new engine, alternator, starter, IAS motor, and the car runs perfectly, I just don't know why it does this when it starts.

Any ideas, I am stumped.