Just purchased a 2000 ssei w/ 107k miles. Car did sit for 2 years however. When I start the car only when its warm it idles really rough for a minute or so, sometimes with a surging idle which causes it to stall. I press on the peddle there is an extremely delayed response sometimes, other times it starts surging even worse. The car also doesn't seem to have the get up it should. I haven't really gotten on it that hard, maybe 3/4 throttle, but I noticed the boost gauge has never gotten above 0 psi. Any sort of suggestion to point me in the right direction would be great. Thanks.

I would start by cleaning the Idle Air Control and Mass Air Flow sensors.

Check the engine bay for vacuum leaks. IAC and MAF don't affect boost.

drain the old gas and put new in?