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I'm not a pro, but i'd say maf or throttle body?

Try unplugging the maf and seeing if that makes any difference?

Or trying cleaning the throttle body and re-allign with vag-com.

Someone knowledgeable will come along soon though....

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Mass air flow. Monitors air going into the engine and tells the ecu which puts more fuel in to match.

My Octaia 1.6 2000 reg was suffering similar problems. My brother is a mechanic for the main VAG Dealers here in Dublin, Ireland. He suggested it was probably MAF however on closer inspection there was a simple hose between the block and the throttle body housing that was disconnected on connecting this the hunting stopped. Hunting prior to this was idleing at 900 and increasing to 1000 - 1100 while hunting no just idles normally at about 950 - 1000

Hope this helps.