Like many of you I've been experiencing less than enthusiastic throttle response from my 1.8T Drive by Wire. I've done many of the recommended easy fixes. Some of which improved throttle response.
I have no idea (other than instinct after reading Passatworld threads for the last 2 months) why it worked for me but it did and am passing it along w/all the usual "do it at your own risk" disclaimers.
Yesterday the following occurred on my '02 1.8T AWM with 295km by resetting my Passat's computer to clear some codes:
I unplugged both my battery leads - IMPORTANT - negative first as always.
After 10 seconds I touched the 2 leads together for 20 seconds.
Left it alone for 5 mins and then re-attached the battery leads to the battery - IMPORTANT - positive first
Performed a non-vagcom TB alignment by turning the key to the "on" position w/o starting for a min of 3 mins (cable is coming as a Christmas present from the Mrs.)
Started the car after 3 mins
Result: Throttle response from low rpm is greatly improved. Even at cold engine temp. (I live in Canada and generally will warm the car for at least a minute in Winter)
Your mileage may vary!