hi there 93 classic wrx having random boost between 0.5 bar and 0.75 bar changed my maf sens and the problems started got the sens from a breakers yard phoned them and they think it may be off a legacy boxer non turbo!! would this be causing my probs?

 

any one?????? thanks in advance

 

whats the code number on the maf bud? needs to be a green label starting with a big `A` iirc