I put a bunch of miles on my 1.4T this weekend on Labor Day vacation. But I have noticed at take off from a dead stop it chugs a little bit, almost like the front end is vibrating. Kinda like if I took the traction control off and just mashed it, the front end kinda goes loose. I only have like 1500 miles on my Eco and it is bothering me that I go to take off and I can feel it in the front end.
just hit it with carb cleaner idling cold and see if the idle changes.You could try it warm to.At any rate if the idle changes the valve cover is no good.