This may not solve *your* problem, but I'll post it just the same...
I had a similar lurching problem with my Alfa Spider, and I discovered
I had torn a small section out of the rubber air intake hose (which goes
from the air sensor to the plenum). I figured that when I was in first gear,
the engine was torquing the crack open, letting in extra air the sensor
wasn't aware of and not able to compensate for. When I tried any other
(smaller) gear, I didn't have the same problem. I was able to
test my theory by putting duct tape over the tear -- which did take care
of my lurching and stalling... so I then purchased a used replacement
intake hose, installed it, and haven't had a problem since.
I would expect your 4kQ to be Bosch FI just like my Alfa Spider and
80Q... but from the story, I could not tell if you meant that you had a
tranny problem or FI problem.
Good luck and Ciao -