The Me7.5 ecu found in the DBW 1.8T uses a torque demand system based on a software model, The throttle wont work like a cable driven car, ie it you put you foot flat down on a dbw car when its sitting ticking over the butterfly will only open up a small amount to meet the requested torque load, if you put you foot down in 3rd gear doing 50mph the butterfly will fully open up as the torque request will be close to 100% load. I doubt it is the ECU, But I will have a look to see if I have one knocking around, I think your ecu was a 018DR with the hardware number ending 887?
Did your codes come back?
You need to check the map sensor aswell, using blocks 115 with vagcom you will see if it is working at idle, I had one the other day which would not log less then 1040 at tickover and with the engine stopped, when we fitted a new one the MAP was at 1020 and raised/droped when we bliped the throttle..
Plus check the MAF aswell try running it un-plugged.
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