Quote Originally Posted by GA_Teg
B, from the sounds of it the ecu is in limp mode. That is the reason you can't go over 4k. As for the fuel trim it could be any number of things from a fuel pump, clogged filter (not enough pressure), etc. I would pm Vteckidd and ask him for a route of action to see if it might be easily fixed.

close to what i was going to say, also if it doesn't sound like your going on all cylinders maybe a bad injector or pump. have you ever changed the filteR? do that too, its like 12 bux and take about 10 minutes.