You said that it runs rich and just cant run over 4k. For dsm's, thats always a symptom of either bag ignition (plugs and wires normally) or boost leak. Check every clamp. The ones that go to the intercooler, to the turbo and to the intake manifold. If your plugs and wires are good, I would double check your work and tighten every clamp and make sure they are on properly.