Stalling when restarting

[Eyvind Spangen]

I have a problem with my 200q20v. When I start it cold, it will always
start fine. When it's warm, it will stall upon restarting (runs under
a second and then stalls), maybe I need 3 tries before it finally
fires up with a small cough. If I give it some gas, it will start on
the 1st try, but I know I'm not supposed to touch the accelerator at
all when starting. The bypass valve (Bosch OEM) is brand new, and
replacing that cured another stalling problem, but this problem
persists..

Any tips or what to check?

-- 
E. Spangen
'90 Audi 200 quattro 20v