Does it seem like its missing or stumbling? If it were fuel cut the red triangle on the dash would blink on for a second. I had a similar problem only at high revs and high boost 18psi. The car would accelerate and then stumble then accelerate etc.. I changed my plugs and tried different gaps that helped but didn’t solve the problem. Finally I talked to Jeff Watson at J-marks and he mentioned that they had success at changing the coil packs. So I bit the bullet and replaced all of them. Problem solved. Coil packs do ware out.