i can't figure out what can cause this but i can boost fine but when i go back into vaccum, about -10, i would feel this weird jerk in the motor like something pulls back on it for a quick sec and then it's fine. could it be shaft play? the wheel didn't really have any play but it was used

 

check for oil on/in your far left injector if you have a breather filter on your valve cover. use a air gun and blow it all out.

 

take the injector out completely?

 

no, just check around the clip for oil if you pull the clip off you may see some oil in the prongs. blow out all that oil thats trapped in there. Thats what happend to me.