This apears to be random, and does it in any gear, and any boost level.

My car will pull timing out of nowhere in the higher rpm band, and the narrowband a/f gauge will go full lean. Im curious if my fuel pump might be going out? This even does it at 10psi. I don't understand it, friday it was dynoed at 12.2:1 a/f @ 13psi in the high rpm ranges... WTF?!