Cleaning IAC

Snorkus, filters, throttle bodies and intake manifolds.

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Shaggy
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Cleaning IAC

Post by Shaggy » Sun Nov 28, 2010 5:39 am

From what i understand i need a new gasket for after i take it off and clean it. Also what exactly is the process for cleaning it. What should i use to clean it and does the iac itself go bad or is it just the motor. What kind of damage should i look for when i clean it to know if i should get a new one. Should i just get a junkyard one? A new one is $500+ and thats more than i bought my car for lol. I took the motor off and cleaned it a while back and noticed there were some score marks on one side of the little round metal selenoid and inside the motor on one side. Im sure thats not good but is it that big of deal? Sorry for all the questions but im just tryin to do my research before i do this. Its my only car so i cant be stuck without it.
90 2.2 N/A legacy awd wagon with outback struts.

Legacy777
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Re: Cleaning IAC

Post by Legacy777 » Sun Nov 28, 2010 11:48 pm

If the old gasket is torn or bad, you should replace it. I have reused the gasket if it looks ok. The IAC valve can get gummed up with carbon & oil, which is what the cleaning is supposed to help.

Can you take some pictures of the score marks you talked about?
Josh

surrealmirage.com/subaru
1990 Legacy (AWD, 6MT, & EJ22T Swap)
1997 Impreza OBS

If you need to get a hold of me please email me rather then pm

AWD_addict
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Re: Cleaning IAC

Post by AWD_addict » Mon Nov 29, 2010 12:03 am

I used some MAF cleaner. It worked fine with some q-tips to clean out the IAC, the idle became smoother.

http://www.crcindustries.com/auto/conte ... x?PN=05110
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Shaggy
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Re: Cleaning IAC

Post by Shaggy » Mon Nov 29, 2010 2:54 am

Yes i can take some pics, and i will get to cleaning as soon as i can. Thanks to both of u for the help my car and i both appreciate it. I will buy some of that maf cleaner to do the job forsure, im sure that my maf could use a cleaning too. Wouldnt hurt anyways. Thanks again, ill let u know how it goes and ill take some pics of it too.
90 2.2 N/A legacy awd wagon with outback struts.

Mattheww044
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Re: Cleaning IAC

Post by Mattheww044 » Sun Dec 05, 2010 3:49 am

ive been having issues with mine for awhile now. I've just heard to use MAF cleaner or brake cleaner "sparingly". I think my wiring is toast or something somehwere though. Let us know if cleaning helped yours

Shaggy
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Re: Cleaning IAC

Post by Shaggy » Mon Dec 06, 2010 1:35 am

Will do, ive been in the proccess of moving so i havent been able to get to it. But will do it as soon as i can and ill let u know how it goes. I plan on taking some pictures of the proccess also.
90 2.2 N/A legacy awd wagon with outback struts.

Shaggy
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Re: Cleaning IAC

Post by Shaggy » Fri Dec 10, 2010 12:20 am

I was wondering if pb blaster or carburatur cleaner would be safe to use to clean it with?
90 2.2 N/A legacy awd wagon with outback struts.

speedmaxx
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Re: Cleaning IAC

Post by speedmaxx » Fri Dec 10, 2010 2:45 am

sea foam is what I used, it worked well.
93 legacy l
to much to list....

Shaggy
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Re: Cleaning IAC

Post by Shaggy » Fri Dec 10, 2010 3:49 pm

With q tips or did u just pour it in there. Because i need to take it off and clean it.
90 2.2 N/A legacy awd wagon with outback struts.

Legacy777
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Re: Cleaning IAC

Post by Legacy777 » Fri Dec 10, 2010 6:54 pm

Just pour the seafoam slowly into the IAC with the engine running. You could try pouring it into the IAC prior to the engine running and let it sit for a bit before starting the engine.
Josh

surrealmirage.com/subaru
1990 Legacy (AWD, 6MT, & EJ22T Swap)
1997 Impreza OBS

If you need to get a hold of me please email me rather then pm

Shaggy
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Re: Cleaning IAC

Post by Shaggy » Fri Dec 10, 2010 9:54 pm

Ive already done that a few weeks ago. Didnt help much, maybe a little. I need to take it apert and clean it. Thats what i plan on doin and i already have some pb blaster and carb cleaner and seafoam layin around and was wonderin if that would work to clean it when i take it apart
90 2.2 N/A legacy awd wagon with outback struts.

volny
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Re: Cleaning IAC

Post by volny » Fri Apr 01, 2011 3:13 am

I'm having problem locating the IAC (I'm learning...:).

Where is it? My repair manual has shitty pictures and I can't wait to poor that seafoam in it. Is there a specific hose you por it into?

volny
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Re: Cleaning IAC

Post by volny » Fri Apr 01, 2011 3:44 am

Do you poor where this "funny" guy sprays?



sorry its a toyota

Mattheww044
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Re: Cleaning IAC

Post by Mattheww044 » Fri Apr 01, 2011 5:20 am

If you are looking down at the top of your motor (from the front of the car, hood popped obviously), if you look at the throttle body, it will be off to the left. A tannish yellow colored plastic top is sitting on top of the valve and I think the stock IAC has a red sticker on it. Not sure if it matters which hose you poor it into, but I don't see why it would matter.

volny
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Re: Cleaning IAC

Post by volny » Fri Apr 01, 2011 6:08 am

I only have a brief diagram on that haynes repair manual...says one hose is the coolant line, the other the air hose. My kook brain dont get how a petroleum product like seafoam could mix with either. Unless I poor straight into the IAC valve if it's even possible. I also bought a carb cleaner, I may just spray the hell out of it.

Legacy777
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Re: Cleaning IAC

Post by Legacy777 » Fri Apr 01, 2011 5:52 pm

I've got a lot of the different engine components labeled in these pics.

http://main.experiencetherave.com/subar ... injectors/
Josh

surrealmirage.com/subaru
1990 Legacy (AWD, 6MT, & EJ22T Swap)
1997 Impreza OBS

If you need to get a hold of me please email me rather then pm

volny
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Re: Cleaning IAC

Post by volny » Sat Apr 02, 2011 1:25 am

Nice! Useful stuff definitely!

Well I ended up spraying the throttle body and inside the valve with carb N choke cleaner, as well as the maf (which is not recommended I found out later...).

Poored more seafoam into the pcv valve ( I go bit by bit).

Soobie is getting happy step by step!

TurnNburn
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Re: Cleaning IAC

Post by TurnNburn » Tue Apr 05, 2011 7:38 am

+1 for cleanin the IAC. I just did this and holy cow did it make a difference in the quality of my idle. Like many on here, my idle was awful. Low and wondering between 200- 600. It would practically die if i didnt give it any gas at idle. I just sprayed a small amount of break clean down the tube and a little through the intake manifold side since i removed the throttle body for a good cleaning anyway. I could tell there was a point in the rotation of the cylinder that actuates the valve that it didnt want to move very freely, so i just spun it back an forth until the motion was smooth. Be very careful to mark the position of the where the screws that hold the top down go to assure proper assembly because the position of the cylinder does matter compared to the magnets inside. I just took a sharpy and and drew a line from the screw and down the mounting plate so when i put everthing back together the lines matched up and i tightened it down. The idle has never been this smooth since iv owned this car. Right around 700 or so.
1990 NA 2.2 Open Light rally car

kimokalihi
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Re: Cleaning IAC

Post by kimokalihi » Tue Apr 05, 2011 9:10 am

My idle is pretty good but I feel like I should try this anyways. What do you think? Sounds pretty easy.
98 Metro Hatch Daily Driver :)
91 SS EJ20G Engine/Tranny/Diff Swap Build Thread Here
"Your testes are close to your bottom but you still play with them all the time." Jeremy Clarkson

TurnNburn
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Re: Cleaning IAC

Post by TurnNburn » Wed Apr 06, 2011 3:42 am

i wasnt sure about tackling this either since it seems to get so many mixed results about how affective it is and the possibility of damaging components inside. But if i can do it, anyone can. Just undo the two screws on top, mark them first. I removed the hose coming out of the top so i could get a more direct spray inside, i use brake clean. And since i was deleting the coolant lines that go through the throttle body and removing the throttle body for a good cleaning anyway i was able to get the other side of the valve inside the intake manifold too. Im not sure you would be able to get that hole without removing the throttle body, but i didnt check. After soaking for a minute or so, i twisted the shaft that is exposed back and forth until the movement became smooth. Then i just put everything back together making sure that the top went back on in the exact same position it came off. And then bam... all done. After everything you have done to your build, this should be pretty straight forward.
1990 NA 2.2 Open Light rally car

kimokalihi
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Re: Cleaning IAC

Post by kimokalihi » Wed Apr 06, 2011 6:14 am

Thanks. Yeah sounds like a piece of cake without really looking at it.
98 Metro Hatch Daily Driver :)
91 SS EJ20G Engine/Tranny/Diff Swap Build Thread Here
"Your testes are close to your bottom but you still play with them all the time." Jeremy Clarkson

Omega79
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Re: Cleaning IAC

Post by Omega79 » Thu May 26, 2011 7:31 am

Hmmmm.... I've been having the terrible can't track down idle too. I will have to do this tomorrow!
lucas wrote:There were multiple Legacys with 300k+ miles. Jesus will return on a Turbo Lego.

volny
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Re: Cleaning IAC

Post by volny » Mon Dec 09, 2013 3:40 am

2 years later...

I've been having idle issues, so I finally located the iac valve and what I did is disconnect the top of the hose and poor a sh...t load of seafoam in in it. With hose still disconnected and poiting up I started the car.

It took a few crank to get it running, but after that I had the biggest cloud of smoke I've ever seen, the whole place turned into transyvania horror movie flick lol...

Anyway I ran the car and reved it up for a while to get the smoke out of it. Totally stabilized my erratic idle.

3 weeks later idle a lot better, but starts to go crazy randomly on me again (still a lot better than before).

I poured some seafoam into the gas tank on near empty tank, and oil tank...drove the car for a while, fueled up seems to do better now.

I do believe I still have some gunk somewhere.

lucas
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Re: Cleaning IAC

Post by lucas » Fri Dec 27, 2013 11:26 pm

hey man just posted a video of a guy doing it over in the "engine" section check it out.
1993 legacy ss "Shela"

CAV3MAN227
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Re: Cleaning IAC

Post by CAV3MAN227 » Sat Dec 28, 2013 3:46 am

-Link to lucas's video, if needed:

http://bbs.legacycentral.org/viewtopic.php?f=5&t=52917

-Joe
-I'd rather loose by a mile because I built my own car, than win by an inch cause someone else built it for me. Your car, is your story, so don't let someone else write the book. ~Moog

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