EGR Valve stem not closing all the way

How tight should the valve stem be on the EGR valve? Is it supposed to be air tight? My engine idles low and I have low vacuum. While I was looking for a vacuum leak, I sprayed carb cleaner a the base of the valve stem on the EGR valve and the idle and vacuum jumped up. I can see the valve open and close properly when I increase the RPM, so I know the valve is working properly, but I suspect the valve stem may not be seating properly.
Author: jm2576