KennyBoxster had the same problem due to MAF being a "newer" model than what our ECM expected. There is an upgrade to the software, or you can run an older MAF unit.
It took KB 3 MAFs and hours to figure out. There is a report out on it…Kenny transcribed it from German! Now that's devotion to fixing a problem!
Another problem was 2nd gear shifting, slight pause or engine cutout right after shifting. All due to the wrong MAF, or too new for the car to read correctly ALL the time.
We drove around for hours, and it was only intermittent at best. We even unplugged the MAF (do NOT personally recommend that) and it RAN BETTER!
Good luck!