This issue seem to be getting worse - took a very long road trip to drop one of my kids off at summer camp on Saturday/Sunday. While driving at highway speeds everything is just fine however when coming to a stop and idling I'm getting these idle fluctuations more frequently and closer together. Yesterday morning we stopped at a store after driving for about 2.5 hours and my wife went inside for about 10 minutes. I stayed in the car and let it idle. The outside temperature was about 74 degrees and there were no idle dips/fluctuations. Yesterday afternoon when the temperature was in the 80s and up it was doing this quite a lot. I've had the codes read several times and it's not throwing anything.