I too had a CEL for EGR flow. I'd heard that removing and cleaning the tube was not easy....and it wasn't. It was hard for my big hands to reach in there and get the thing off but I do have one tip:
Once you get the EGR tube off, get yourself an eight inch piece of 3/16 inch aircraft cable and a battery powered drill. Chuck the cable in the drill and while spraying solvent in the tube, run the cable in and out with the drill. The cable will fray and come apart which makes it work even better. My EGR tube is now completely free flowing. No spray by itself can get it this clean.

 

thanks for the tip guy.