gap the plugs, see the outcome. If it doesn't work you can always re gap them. I would suggest borrowing robs ones just to check. If this doesn't work:
1. it could also be a clogged fuel filter.
2. Possible vacuum leak on turbo lines OR a hose is split somewhere.
3. 02 sensor??????????????
Also does it do it when you are sitting at 3-4k OR is it under high boost? or both
And when the AFM was cleaned was it 100% checked to be working??
Edit: it is also POSSIBLE (unlikely) that your cat is f**ked and causing air flow issues with the exhaust....