s5 streetported. has like 30k miles.(no air pump or rats nest) i bought off guy in cincy and we put it in, and it wouldn't idle but that was because of header (no back pressure, but fixed) but still once it is revved up to like 3k it cuts out.

do u guys think this is a vaccum problem. or maybe a faulty injector, or maybe something got connected wrong when the motor was put in or anything else it could be cause i'm lost and don't really know what it is?

 

explain "cuts out". Does it hesitate, then pull through the rest of the RPM range?

 

oh sorry, no i mean it completly dies

 

so you go to start it, it revs up then dies? Like it starts, revs to 3000rpms, acts like it is doing fine, then cuts off. Check the AFM.