I have had the problem that my 94 civic ex likes to have a very low idle at stop lights and signs When i first turn my car on the Idle is at about 1000 and stays there. Once i start driving and go to a stop the idle ranges from 300-700 and it bounces from time to time. sometimes i see it hit 900. Shouldn't the idle be at a steady pace and at at least 1000? Aslo when i am just about to stop my idle raises on its own slitley then goes back down. Theses also the problem where when im driving the Idle kinda chokes up for a second. Like it goes up slitley then down then up a couple times. then it drives like normal again. This is very odd? Right now i do not have a muffler on the car as it was junk so im running with just a short strait pipe if that could have any effect

 

I cleaned my IAC valve untill no dirt was coming out of it. It seemed like it helped. after reinstalling it i took it around the block at stops the idle was at 1000 so i thought it was fixed. Drove it again for a farther distance and it's at 300-700 again. Any ideas?

 

I would double check ignition timing and fuel supply(fuel filter etc) if you cleaned your iac its a good idea to reset the ecu<(unplug battery for 5min)