97 Civic idle surges

I am working on this 1.6 non VTEC engine and I am having a problem with the idle. It will run fine until closed loop. Then the idle bounces from 1200 to 1700 rpms with no input from the TPS. I have tested the MAP for vacuum and it tests fine. I have removed the IAC valve and cleaned it, cleand the idle screw port and checked for vacuum leaks found none. Any suggestions?:banghead: Thanks.

If its a manual transmission check your fast idle valve. It doesn't throw a check engine light. When it goes it acts the same way as if a IAC valve going does.