Well..... EGR valve may cause that but i doubt it .... usually it is an older vehicle with higher miles that has EGR problems..... it sounds like maybe a vacuum line problem. Take a propane torch (not lit) and run it along all your vacuum lines whil your car is running. If it all of a sudden idles higher there is a leak there in your vacuum line.... replace it... this is just a very basic start. Describe your problem in more detail so we can help trouble shoot!! Don't mess with the EGR right away.