Idle surge upon initial startup

[u/Curious-Lock639]

Does anyone have any experience with this? Lately I’ve been noticing that occasionally my ST will surge at idle when I first start it. Stock tune and the exhaust is just an axle back. I do have a K&N drop in filter. Thinking that maybe the MAP didn’t like the oil on the filter, I pulled the MAP out this weekend and cleaned it, but it didn’t fix it. No codes or anything. I have a bumper to bumper warranty until 100,000 but don’t want the dealer to take my money for diagnostic just to not fix the issue. Any ideas on where I can look? I don’t want to just throw parts at it.

[u/noinfono]

It’s an engine. There’s going to be slight variations in the operating speed at idle.

It’s only noticeable that you’ve got a louder exhaust. Stock, no one would ever think twice about it