Ok, I have narrowed it down from my O2 sensors, cuz neither of them were hooked up; to my IACV. I unplugged it and let the car idle and it idled at just the right RPM but it caused a check engine light. When I plug the IACV back up the idle went back up to like 2K-2200 RPM. So I now beleive this is the cause.

Can somebody please give me instructions on how to clean my IACV?

TIA

 

Well, maybe it's a little different for civic/integra or different years, but...

On my '95 integra, you unplug the IACV, the "base" idle is supposed to go down to about 450. You have to gently adjust it down so it doesn't die... Then when you plug the IACV back in the idle goes back up to 750 where it belongs.

So get your hands on a repair manual & check out the procedure for adjusting base idle.

 

Exactly - your base idle speed has to be in a very narrow range in order for the IACV to do its job correctly.

If you unplugged the IACV and the idle was 'normal', then you've got a vacuum leak or the base idle speed is set too high.

Have you touched either of the idle air bypass or throttle plate stop screws?

Whats your setup?

Cleaning your IACV is nothing more than removing it and shooting carb cleaner through it till it runs clean. When my IACV froze up on me from being gummed up with carbon and crap, I simply warmed up the engine and shot several blasts of carb cleaner into the IACV port hole - it cleaned it enough to unfreeze it and its been holding fine for over 15k miles.

 

My setup is a BBK TB on a stock manifold and a AEM CAI. https://honda-tech.com/zerothread?id=165216 Look at the 3rd to last post on there and there is a pic of a spot that doesnt have a vaccum line on it. It never had one there and it idled fine before.

Can I adjust this basline without removeing the IACV? I'm not quite sure what you mean by turning it down to 450. Is there a screw somewhere that I cant see?

 

The piece you have circled, I believe, USES vacuum - so the fact that nothing is connected to it should not result in a vacuum leak. If you put your finger over this nipple, is air being sucked into it?

The BBK t-body - how many adjustment screws does it have?

Usually there are two (on a stock t-body): 1 to allow more air to bypass the throttle plate (idle air bypass - used to set the base idle speed) and 1 to keep the throttle blade slightly cracked open from being fully closed in the t-body bore - if it were allowed to seat everytime you let off the gas pedal, it would eventually round out the bore and cause a vacuum leak. The throttle plate stop screw also has a direct effect on the TPS output.

When you unplug a 2-wire IACV, it closes down and should not allow any air to bypass into the manifold - so you don't need to remove the IACV in order to set the base idle speed - you just need to unplug it.

 

Mine doesn't have that thing, I'm not sure what it is... What else is it connected to? Looks like a vacuum diaphragm that operates something mechanical? Throttle dashpot maybe??

You probably have a mechanical stop for the throttle, supposed to be adjusted to only just prevent the throttle plate from wedging itself stuck closed in the TB. Then there's often a needle valve to let a small amount of air bypass the throttle plate. That's what you adjust.

To adjust the base idle you don't remove the IACV, you unplug the electrical connection so it closes. Then you adjust your idle to 450, with a warm engine & no accessory loads. When you plug the IACV's wiring back on, it opens & controls the idle to 750. But these details are all a little different for different cars/years.

 

So, I need to unplug my IACV, set the idle at 450 then plug the IACV back up?

My TB only has one screw on it; under the butterfly (part the cable connects to). The plate is as low as it will go and I tested my TPS a while back and I got some off the wall reading that was double what it should be. I posted a topic on that a while back, but nobody gave me an answer. I bought another TPs from ebay and it got the same readings. Neither of them threw a code until it wasn't in the "all the way down spot"; where it was reading double. So either I have two bad TPs sensors and I need to try to get my money back from the dude, which Im sure it is too late or there is another problem. I need to fix this high idle before the warranty on my tranny expires. (mechanic said he doesnt want to take it apart under warranty until I fix my idle. I have about 1K miles left for the warranty)

 

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by B16CRXT &raquo;</TD></TR><TR><TD CLASS="quote">So, I need to unplug my IACV, set the idle at 450 then plug the IACV back up?</TD></TR></TABLE>No, first you need to get your hands on a Helm book for YOUR engine. Then you'll know whether the base-idle procedure is the same as my '95 B18C1...

Really, your description sounded to me like the base idle was set wrong. Maybe I should have never posted the procedure, since I don't know if it's the same for your B16???

 

Where can I find the helms for my engine? This specific part of the manual. I cant afford to buy the entire book right now.

 

google search

 

A ehilr back I was told there was a screw or something under the plate on my TB (it is where the missing link would go in a cheap turbo setup) that would adjust the idle somehow. Is there any truth to this?

 

thats the problem im having also. whats the best way to set the idle. im either thinking of screwing it in all the way and adjust out or screw it out all the way and adjust in. dunno though

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by EE_Chris &raquo;</TD></TR><TR><TD CLASS="quote">

If you unplugged the IACV and the idle was 'normal', then you've got a vacuum leak or the base idle speed is set too high.

Have you touched either of the idle air bypass or throttle plate stop screws?
</TD></TR></TABLE>

 

I went exploring and found out there is no scrwe inside the top of my TB (missing link portion). There is however a HUGE vaccum, which, if uncovered, drops idle substantially. So I proceeded to try to lower my idle by my idle screw...all this did was make my throttle plate stick, soI put that back to original position (lost an allen wrench in the process...damn tiny things).

Can someon please clarify for me what you spray carb cleaner into to clean out the IACV? Do you take it off and spray into it or do you leave it on and spray into something else? Please HELP!!!

 

you take off the bolts and spray it clean. you will see a screen, prolly dirty. i fixed my problem by adjusting the idle screw and checking it on a tachometer