UPDATE.... CEL came on again today, 4 codes (P1335 and P0404) they showed up twice.

This is two days after taking out EGR cleaning (see above) and reinstalling. Should I just put in the new EGR and see if that solves the problem, or take it to dealership and see if there is another cause to the problem (leaking egr cooler, etc.) I really do not want to put in a brand new EGR and then something else cause it to fail. Any help is greatly appreciated!