So currently all I have done to my 2016 Veloster Turbo (automatic) is a cat-back exhaust and an air intake. The issue I've been having is when in open throttle and in higher gears around 4k, it seems like the turbo flutters while accelerating and sounds like it is surging. This is followed by the car going into limp mode, low power, and the turbo doesn't spool until I turn the car off and start again. Not too long ago I installed the MAC BOV Solenoid upgrade from kdmtuners, but didn't fix my problem. There was a previous forum post I found discussing this, but no solution was found. I'll leave a link to a YT video to a 13' Veloster having a similar sounding issue. If anyone smarter than me can help out, it'll be greatly appreciated.