Guys I'm having the same exact issue where the startup is alot louder than before then the check engine came on and the same codes for the secondary air injection banks 1 and 2 came on. The shop thought they fixed it by replacing the air change over valve as they said that was a failed part and i wasn't getting any air through the vacuum system. That for some reason quieted the car down a bit but after 2 days I still have the check engine light coming on with the same codes....what to do

 

There are 3 check valves-find out which one they replaced. If it was a dealership I would be all over them. There is a process to check each one. I changed all three just to get it over with.