revs up and down then dies

I need help. I did a h/c/i swap and now my car revs up and down at idle and has a whining sound sometimes and will die if it sit to long at a light I pulled a code on it that the egr is erratic or has insufficiant airflow if I pull the pcv valve the whining goes away and it idles better but ive replaced the pcv and I'm pretty sure its working right I have 10" of vacuum and it runs great past 1100 rpms can anyone help me?!

Alright thanks guys do you have any idea where the whining noise might be coming from I have checked all my intake bolts everything seems tight it almost sounds like its not a vacuum leak but maybe theres a valve of some kind half way open and im getting some blowby but the noise is coming from the back of the engine somewhere so I dont know what that could be