Do you have a heated front screen ?, if so put it on and then turn again see if it cuts out then.
I would also have a look for any air leaks now, it really is easy to fix/check/clean the iscv even easier if a mate helps who knows his way around cars as they are very simple.
You could also try pulling the 2 amp VILOET fuse marked KAM, for a minute, this will cause the ecu to enter relearning best settings routine.
The steering normally does have a fluid pressure switch, so check connections, look especially on the crank case vent valve and pipes to and from it, follow these and there is a famous T piece that collapses and cause issues.
tabetha