Off the top of my head possibilities are: knock sensor problems, AFM problem.... I'm not sure if the oil pressure sender being disconnected would cause that, but I think it's unlikely.
Did you get the knock sensors connected? Did you drop the AFM? Did you perhaps spray anything into the AFM (such as a MAF cleaner or brake cleaner)? Have you checked for codes now that the you've had the car running?
As for the oil pressure sender... Follow the yellow arrow.
Oh, and the cold start injector ONLY adds fuel WHILE you are cranking. In all but the coldest conditions the car will still start without it, just not without some trouble.