99 Dodge Intrepid 2.7 misses at idle

Misses all the time at idle smooths out immediately when engine speed increased. Check engine light on. Had dealer check it out. Error code says miss on #1. Swapped out injectors and coils. Did change intake gasket and good for couple days. Dealer at a loss plus called Chysler no leads. Only other thing of note was changing battery just prior to this problem showing up.

At a loss as to how to proceed other than have dealer dig in which I am very reluctant to do.

did they also check the plugs and change them...

You could one of three things wrong; 1) your plugs are severly worn and/or not gapped properly. 2) You have a vacuum leak or 3) Uneven or low compression. From what you said earlier, you have a vacuum leak. Best way to find that leak is to spray a mist of water on the manifold until you see bubbles forming. When you see those bubbles, you have found your leak. That or it's possible that the gasket worn torn when it was installed.