Calling all Techs. I have an intermittent problem with rough starting idles. This happens every few months, more often when cold or wet. There has never been a CEL, so no codes. The problem always resolves within one to two miles of driving. It is characterized by a rev to about 1500rpm followed by a low rev (700rpm or so) almost choking out then another high, and persists until car is warmed up a little. I have read that it could be an ICV, but I don't see one listed with 2.7T parts. My other thought is the MAF, but this would trip the CEL I thought. Any help would be appreciated.

 

idle air control valve would be one place to look at it, but i'd vacuum test and look for leaks. i get the same thing from time to time, and mine finally popped a P0301 code when i let it sit and idle while it was stumbling, but i'm assuming you've already thought of plugs.