The dealer should be able to look at the position of the iac valve and determine if the valve is commanded to close. If this is so, then air is getting in from some place such as the intake gasket. He should also be able to watch the fuel trims to see if they are lean. Try and spray some carb cleaner around the base of the intake and listen for the engine to change rpm's. If the dealer is doing this he will be able to see the o2 sensors go full rich as soon as he sprays the intake( if there is a leak). You will not believe how fast they react. This is how I found the leak on my girls trooper. Watch the 02 voltage and hit it with carb clearner of brake cleaner. Be careful as not to start a fire. Sure is hard to type with one arm. Just had my ac joint surgery. Feels much better though. Hope this helps out. .

Andy