I have a 2000 ex 1.6 vtec, during idle shell go back and forth between 800-2000 rpm's, when im driving im fine its only idling. i took the IAC off it looked clean but i cleaned it again anyway. Think its bad? or could it be something else?

 

try bleeding you coolant system and change the pcv ,......and if that dont work it could be a bad iacv.

 

you coould also try cleaning your iacv.

 

I cleaned the IAC already, ill try burbin the coolant system and see how that goes, thanks for the suggestions!

 

I have the same problem, how do you bleed the cooling system I have a 1997 civic ex.

 

there is a post here on how to ,..let me see if i can find it.

 

i had the same problem found out i had a coolant leak and just needed to keep the resivour topped off and the problem stopped check to see if there are any cracks in your radiator

 

here you go

https://www.hondacivicforum.com/foru...ad.php?t=41650

 

OK so i fixed the idle problem, but it was wierd how it was fixed. I tried bleeding the coolant system, no air didnt work, IAC was already cleaned. I did the trick where you bypass the coolant lines going into the TB bleed the coolant system again and some how that fixed my idle problem, when i start it idles at 1500 till it gets warm then drops to 900 were it stays. Dont know if that will work for everyone with this problem, but seemed to fix mine

 

Thanks Tony but where is the bleeder screw on a 1997 civic