I’ve seen several threads on this problem but can’t track down the issue. Newly built N12 motor with 100 miles on it so far. Runs great while driving at any speed/any gear. Sometimes when I come to a stop it idles rough and may stall occasionally. Sometimes I get a CEL for P115D. Checked for leaks (spraying cleaner) down stream of the MAF and around the valve cover. Couldn’t find any kind of leaks. Pulled out both vanos solenoids. One of them was dirty and missing oil screens. Swapped it out for a spare that I had and also switched them to help diagnose. No change there. How can I test the MAF sensor? I have an OBD Link MX and the MAF reading sits right around 0.58 lbs per min.