Hello all,im new to this so please bear with me,I have a 99 golf with a AGU engine,i bought the car off my brother and i know its been looked after as he is very particular,it has a decat pipe,cone filter which i may change back,and we think at some point has been remapped cos it pulls REAL stong and boosts at 1.1 bar,but now it seams to of lost some boost and feels uneven while acelerating its throwing up fault codes 16514(po130),00561,mixture adjustment adaptation limit exceeded and 16486 mass airflow sensor-g70 signal to low(po102) intermittent.I think i need a new Lambda sensor and MAF,my problem is genuine dealers want a fortune for these parts but i dont want cheap ones that fail in no time at all.Are there good reasonably priced ones out there?and where?I work with marine engines and plant machinery so have a good understanding of engines but not so much of the fine electronics involved here.Any help would be very much appreciated,Thank you in advance.