I have a MAF reading at WOT and full boost of around 80-90 g/s of air when it should be up around 170 g/s. I have replaced the MAF, checked for any vacume or boost leaks, and switched out the ECU with a stock one, it still doesnt go about 80-90 g/s of air.

What could be causing this?

 

EDIT: Also, due to this, it is running very lean. P0171 code whenever it is run under a slight load (ie. on the freeway.) Pings heavily under boost, it has good quality 91 oct. gas in it.

 

Bump anyone? this issue caused a melted engine and an entire rebuild... of the 4 shops i have brought it to, 3 of them finally refused to work any more because they are stumped and the last one just wants to guess and make money....