06 A4 2.T Quattro 86,000mi. bone stock

Under moderate to heavy accelleration (typical aggressive on ramp merging) the car will pull hard at first then fall flat on its face, almost as if it overboosts and goes into limp mode (but no gauge to verify boost spike). After that happens it will remain way down on power until the engine is restarted, then it runs great until the next time I boot it. Seems to happen easier in the higher gears/under load. When it happens the car still runs smooth, seems fine on gas and is quite driveable.

CEL was already on for an evap code previously and I dont have access to vag com so I cant be sure if this problem is accompanied by its own code.

Any input? N75/wastegate actuator/related vac hoses? Im quite familiar with turbos (80's Buicks actually), new to Audis.