RPMs at cold start approximately 1500 rpms, slowly raising to 2100 rpms, after a few minutes it will start surging from 1100 to 2400 rpms, After few more minutes will surge from 1200-1400. Then sometimes it randomly change back to surging from 1100 to 2100. If you disconnect the IACV plug when surging from 1100 to 2400, it drop back to surging from 1000-2100. When surging from 1200-1400, no change is noted in RPMs (or therwise) when connecting/disconnect the IACV. Surging continue when driving under rpm.