Vacuum Leak? codes p0306, p0421, p1177
 

Hi, I have a 2000 Audi A6 2.7T 6spd. The issue I'm having is on and after my 2nd gear, when i floor the gas after 2000 rpms the car jerks a lot. I took it to Autozone and they gave me these troubleshoot codes on my check engine light. I changed my spark plugs 3 months ago and this recently started happening. Is it a vacuum leak? are my turbos going bad since the problem happens after 2000rpm? bad DV? or is it a cause of a bad cat converter causing cylinder 6 to misfire?