ok so ive done some work to the bus (a.k.a wrx) but even before it had spike also, the work i did to the wrx tho is :
-td05
-STi t.m.
-450cc injectors
-3"ss turbo back
-fuel pump
-pod filter

now im getting my tune done soon (like wen i get my licence bak) nd im wondering if the tune will fix xum of my spike, if not is there a way to reduce it a bit, i kno if i put an electronic boost control it would but dont no if that will stuff with my tune,