97 stock Civic Idle problem

I have a 97 Civic stock 1.6 non vtec and im having problem with the idle. When the car warms up and when im only in park or nutural, the idle goes up and down in between 500 and 1100 rpm. When i take and plug the IAC (idle air control valve) inlet hole the engine runs fine. Any suggestions on what the problem is. I tested for an intake leak w/ propain also i used intake cleaner it the inlet hole to the iac. I recently got a code for the iac and then i had problem taking off in gear. it sort of studdered. i cleared the code and the studder was gone. Any help will be great. Thanks

Did you manage to sort out your idle problem as i seem to have a similar prob. My car gets warm then the idle jumps from 1000rpm to 2000rpm and back to 1000 again. was it the ICV as i think that is the prob with mine.

pull off the IACV and look at it. check for tears and clogged screens. replace or clear as neccessary.

Ya i Did. I just remove the IAC and it fixed the problem. Actually i just replaced the whole throttle body.