Well, I have inherited the care of an '01 New Beetle through marriage. This little girl runs great all winter long, and runs great now that its cooling down a little bit around these parts. However, she had attitude all summer long. Can't seem to figure it out. Symptoms are a general loss of power, surging, and a generic P0171 DTC. The turbo still spools and sounds really loud when its surging. Twice she lost all power and the EPC light came on, had to pull over and restart her. I recently changed plugs, air filter, cleaned the MAF and the throttle body. Wife says its happened every summer since like '08. Sometimes the turbo seems to kick in pretty hard under moderate acceleration, just from my own observation. I don't have time for any hide and seek right now so I thought I'd ask in the forum here. Any helpful hints would surely be appreciated. Thanks in advance.