Idle keeps Alternating from High RPM to Low RPM

[Contingnecy]

I just got a 1996 Honda Civic LX that had been sitting for awhile.

So far I have:

Changed Spark Plugs & Wires
Changed Transmission Fluid
Changed Fuel Filter
Changed Battery & Terminal Clamps
Flushed Radiator

Anyways when we got it, it had an idle problem once it warmed up. It would alternate back and forth between regular idle speeds up to about 2.5k-3k. So I searched around and read it could be the IACV so i replaced that. Now its doing the same thing but on cold start too and its starting to make a sound like a high pitched whistle as well. Anyways I have no idea what it could be. Any help would be greatly appreciated

 

[203CT]

I heard a bad IACV can cause fluctuating idle. Try cleaning it.

 

[EJwood]

I had the same problem with a previous swap, i cleaned out the IACV and FITV. Along with that I also replaced the intake throttle body gaskets and this solved my surging idle problem.

If you are hearing a whistle this could be an indicator for a loose/broken/missing vacuum hose or vacuum leak. Look for broken lines, you might be able to spray break cleaner or soapy water to help you find the leak.

 

[Contingnecy]

I heard a bad IACV can cause fluctuating idle. Try cleaning it.

If you read I said I've already replaced that.

I had the same problem with a previous swap, i cleaned out the IACV and FITV. Along with that I also replaced the intake throttle body gaskets and this solved my surging idle problem.

If you are hearing a whistle this could be an indicator for a loose/broken/missing vacuum hose or vacuum leak. Look for broken lines, you might be able to spray break cleaner or soapy water to help you find the leak.

I've replaced my IACV and i'll try cleaning the FITV and see how that goes. And i'll try the break cleaner trick for vacuum leaks. Thanks for the suggestions for places to start

 

[SlammedEG]

f*** all that s*** take ur intake off in ur throttle body there are two holes on the back side put ur finger over the bottom one im pretty sure its the bottom hole it will stop than find some thing to plug that hole with that wont get sucked thru it really dont matter if it does tho cause it goes down into the fast idle valve . everyone thinks im stupid for doing this but it stops that damn annoying idle, did this on my teg, ef ls, and my car now

whatever you put in there has to be flush so the butterfly can move !!!

or propper way to fix it is adust the fast idle valve in link below
http://www.clubcivic.com/board/showthread.php?t=181501