Have a 1988 Civic LX. After car warms up I will get an occasional low idle bobble issue. Will be sitting at a traffic light and the idle will start bouncing between 500 and 750 rpms. The engine then corrects the issue back to normal idle, but it can reappear. Sometimes having the AC on will aggravate the problem. The kicker is it doesn't do it all the time. I can get to the next traffic light and have no issue even with the A/C on. Have changed oxygen sensor....temperature sensor (which was bad)...have cleaned the idle air control valve screen....have adjusted the timing after mechanic changed distributor and didn't align it properly. Plugs are new too. Car has no problems starting and idle doesn't surge either. Car runs fantastic...other than this problem. Is it worth trying to remove idle air control valve and soak it good? Any ideas would be greatly appreciated. I am NOT a mechanic, but do have a good one. He's running out of ideas. Also no codes are being generated either. Thanks!