So after much bleeding of the coolant and cleaning of the IACV I still have horrible, bouncy idle. (in my 88 CRX HF w/ d16a6 swap)

I took off the intake and checked in the TB, the port in the upper left hand corner of my TB was sucking air like no ones business... If I partially covered it, down went the idle to normal levels.

Soooo, I don't have a thermal idle valve in the normal place (directly under the TB) and was wondering if you fine people on HT could help me discover the source.



That pretty much sums it up. Help out a fellow honda owner for the love of all that is holy, I'm tired of sounding like I'm trying to race every person who pulls up next to me in their mini-van.

 

ive heard quite a few honda's do this. idk what it is but mine has a similar problem just not as consistent with the climb and fall

 

if you get a check engine, check haynes on how to adjust the idle screw. if you dont get a light make sure your hoses are okay and adjust it anyway!

 

Super fail guys....

It's one of the idle valves. It let's air in when the engine is cold, it's not operating properly so it is still letting air in when it's warmed up.

I just need to know which one.

 

upper left corner is IACV, take it off and clean iacv out and see if that helps, if not try a working iacv and see if that helps. ive also heard that tapping on the black cylinder on the back of the iacv with a wrench sometimes tells you if its messed up so just give that a try also.

 

and you said about the FITV, if it only has one whole in the tb then it doesnt have a FITV, my z6 tb doesnt have one, i think only b series do actually could be wrong tho

 

Ahhh, thanks, so I guess I swapped to a bad IACV. That would suck.

 

Sounds like you have a vacuum leak in the intake manifold somewhere, so it's sucking in air from somewhere other than where it's supposed to.

Here's a post from my thread about my bouncing idle:

 

mine was more complex, but i removed the ivac plug, douched it with wd-40 and my problem went away and it is a smooth idle..

make sure the plugs are in the right order, smooth as silk

4321 (block)

12 (cap)
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