Sorry, I had a flu, had to postpone all works for a few days
It's -4F in Moscow, quite cool
Yesterday we cleaned the throttle body and the IAC valve and checked wires (as much as possible). It stopped stalling a day before, so it's impossible to say if we did any good
Today I ran about 100 km, no sign of stalling. So I keep my fingers crossed and ordered NGK spark plug wire set and a fuel filter as well just in case to be sure that we missed nothing.
By far no sign of stalling
Unfortunately, we haven't found the reason of failure
Thanks a lot for your help, guys!