A properly working EGR and the EPS should have nothing to do with your idle, unless the valve is sticking open, or leaking vacuum. The EGR allows exhaust to enter the intake only while driving and the amount of the opening depends how hard your foot is on the gas. The idea of putting spent fuel into the engine is to lower combustion temps, there for lowering NOX emissions.

 

I pulled codes when I first got the truck I got an egr fail to open and something else I don't remember. That said I checked everything again and when I put the new egr in I accidentally bolted the little electrival bracket behind my block off plate. Doh. Running much better now still idling a little high on occasion. I have to use truck tomorrow so I will update again later thanks guys.