Hey Brad.
Now I don't know loads like the gurus on here but I have learnt a bit since being here.
It's my first turbo car so didn't quite know how they worked until I read lots on here.
My car run like a bag of siht (1.8t a3 quattro) when I first got it. It wouldn't hold boost and when it did it was jerky it and would just dump boost then start boosting again randomly. So got a mate to scan it... I got check maf fault codes and check secondary air intake fault codes.
So started buying new parts to rule stuff out in this order...
Got a new forge 007p (original was a standard one) still ran like siht.
Next was the maf (a proper Bosch one) and it made a massive difference, ran smoother, better mpg but it was still not quite right with the boost but better. So got mate to scan again and no fault from the maf came up so that was a relief to know the maf was working as it should being a new one.
So was advised to get a smoke test done to check for boost leaks as I had already checked the pipes myself and couldn't see any split pipes.
I took it to R-tech and did the smoke test, the pipes under the inlet manifold where leaking. I was then advised to get the Oil Catch Can mod done to get rid of all the crappy little pipes that leak over time.
The oil catch can mod is great because you get rid of a load of pipes and end up with 3 pipes so much easier to detect any future boost leaks. Also my intercooler pipes where loose so was leaking there too.
Anyway after all this the car is running sweet, holding boost and just awesome to drive now.
With all that said my advise (take it or leave it) is get a new maf (bosch one not a cheap one) if you don't know how old the one you have on now is, cause if it's old it's probably temperamental or ****** then get a smoke test done to rule out boost leaks.
If it still plays up after this then I dunno lol.