What are the symptoms? the boost lines are always a good quick thing to check and usually an easy fix (so Ive heard) but if its revving freely and not moving could be transmission related, if its falling on its face when you try to accelerate it could be a number of things but less likely to be a boost issue. if its driving fine just feels sluggish like a worn out NA car then could be a boost clamp came loose or a restriction somewhere. if you can put up a more detailed description of what its doing we can maybe help you narrow it down. first things to check would be your boost lines, turbo clamps, noisemaker, and air filter.