Boost leak

[JonnyX]

Anyone have any bright ideas on how to test for a boost leak (apart from getting an
AWE pressure tester - I don't have access to a source of compressed air). My car
is feeling a bit hit and miss at the moment. Lambda correction values in block
32 show -5.5% correction on both banks at part throttle which means I am running
a bit rich. MAF logs are 260 g/s + at WOT which makes me think the MAF is reading
true - perhaps I am leaking some air before it enters the cylinders? Any adivce?

Thanks,

Jon