I just went out for a drive, a quick blast near by on a dual carriage way. Got to a set of lights and pulled away, the car stuttered a bit and then got worse. The car will now not go past 4000rpm and will only build 5psi of boost. I have had a quick look in the engine bay and all the hoses seem to be secure. The car will still drive but it feels like 80% of the power is missing and someone moved the limiter to 4000rpm. What could this be? Really worried its something bad.... Any advice would be much appriacated.