My engine is 9a with EURO k jet FD and KR ignition ecu and auxilary air valve instead ISV. Whem mixture is lean rev is 1200, but when normal rich is about 2000rpm. I have blocked AAV, but hot engine idle is 2000rpm. I tried to adjust (close AAV hole), but revs didn't decrease. Also I tried to retard ignition, idle is still 2000rpm.