Meow? (NAC but VAG diagnostics)

[tihol tiholov]

I'd like to thank everyone, who quickly answered my plea for help.  For the record - the cat seems fine @ 229K kms and see-though, no rich running traces.
Most opinions point to MAF as the cure for the cold-like symptoms.  Wish I knew what resistance on a voltmeter would point to its health/sickness or what would be another way to tell.  Upon visual inspection it looked clean and in one piece.
Second place - 1 vote each was for coil pack or cyl. coil - that's on a turbo.  This is NA engine with a common coil pack for all 4 cylinders - again, I'd appreciate if anyone knows how to check that one.
I have a Bentley but not the full pro version, will look more into it and relay results.
Any other opinions greatly appreciated.
MAC: In the meantime the Typ 89 keeps on going even with occasional blue smoke.
Thanks everyone,
Tihol

TT