update...
I didn't unbolt these 3 bolts.
I just cleaned with brake cleaner, the throttle body, very carefully, which looked very clear.
and i didn't pressed brake cleaner through ISC motor, as i didn't wanted to
get in trouble, 1 in a million.
anyway, i installed all back, and idle is very-very stable.
so problem solved.
According to service manual, the 6-pin connector of ISC, must measure the resistance of 4 coils inside. so , in pairs, 1-2, 2-3, 4-5,5-6, and all of them worked at 38 Ohms.
According to manual, these updated ISC value is about 40 Ohms.
So everything good.
I just wanted someone of you to inform me, if he ever opened in parts,
so noone did it.