Cleaning IACV, FITV and TB

[mtnwkr]

I was having some issues with my car Idling at random spots when In neutral. When I would push in the clutch or throw it in neutral it would drop to 1000 rpms, and sometimes bounce back up to 1200-1500 and stay there, and other times it would drop back to 750 where it should be. I also had a pretty consistant miss at idle that I thought was unrelated, but cleaning the two valves solved that too. The whole process took me about an hour and I'm more than pleased with the results. First thing is to get a mocha from the cute coffee girl down the road. Take off your intake, and strut bar if you have one. Those will just get in your way and make the job harder. Be careful of the cruse control cable while you are working in that area, you don't want to kink it or bend it. With those out of the way you can easily access the three 10mm bolts holding the fitv on. Go ahead and pull it down, no need to remove the hose. There are three little rubber o-rings, you can see in my pic that one was left stuck to the bottom of the t/b, make sure they are all seated properly before re-installing. On the end of the fitv there is a brass plate with two 8mm bolts holding it on. remove that plate. underneath that plate is the white valve body that comes loose and causes the vacuum leak that causes your idle to hunt. You can see in the pic that on both sides there is a little notch for a screwdriver for tightening it up. I just used a small flathead to spin it. Mine spun about one and a half rotations before it was nice and tight. Thats it here, nothing to clean. re-install the plate, wrap it in a small towel to keep it clean, and set it aside for now. Next is the IAVC. With everything removed so far its pretty simple to get off. First unclip the harness. Then on the back side of it there is two 12mm bolts. The longer one is on the bottom. Remove the bolts first, then remove the two coolant hoses. I was able to pinch the clips and slide them down with my fingertips, but a pair of needle nose pliers might be needed for some. The hoses came off easily. In the pic you can see all the crap clogging the screen, and the body filled with black buildup. Thats what you need to clean. With it completely removed from the car, remove the rubber gasket so it doesn't swell from the cleaner. Fill it up with carb cleaner and let it sit for a minute. spray it out and repeat a few times. When mine was done the screen looked shiny new and the valve inside was white and clean as snow. Now while you wait for it to dry grab an old toothbrush and your carb cleaner and clean your throttle body. Hold the butterfly open, spray it all down and scrub both sides with the toothbrush. clean the whole thing out well using copious amounts of carb cleaner to break up the deposits and rinse them out. There are two little holes that lead off to the IAVC and the FITV, spray those clean also. Now re-install everything, reset you ecu so it can learn any changes you've made by cleaning up the idle, and enjoy how smooth your machine runs.

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[EvenStar]

cool, so does this fix our "bouncing 1000-1500rpm repeat" idle when we warm up our car?

[hondadude]

yeah, crank that FITV all the way down; kiss the warm up fast idle goodbye.

[Homesickelian]

No sarcasm here or anything but can you explain honda dude?
what can screwing to far do? Cause I might perform a little maintainance by cleaning the IACV and FITV.
I don't know about the IACV though cause I'm having a bitching time getting the coolant hoses off in that cramped space.

[mtnwkr]

This is how the FITV works..."At room temperature, the wax in the enclosure is small enough so that the needle is pressed in by the spring loaded valve, thus letting in air through the ring-cap and increasing the idle. The needle sticks out 6mm. As the temperature of the coolant rises to about 150F, the wax expands and the needle eventually protrudes to about 11mm at around 220F. The force of the needle on the spring keeps the valve closed. If the ring-cap is loose, there is not enough force to keep the valve closed thus letting in air and raising the idle when not necessary."

Makes sense then that if you "crank that FITV all the way down;" Like hondadude says that it wont work anymore. I'm just saying to tighten it up till its not loose, witch will stop the vacuum leak causing the idle problems.
I respect your knowledge hondadude, But I've read many tech articles explaining this fix, and not one saying that they lost their fast idle at startup.

http://honda-tech.com/zerosearch

[mtnwkr]

I should add that My car warms up now around ~1600 rpm's.
The same as it always has.

[trboeclpse98]

I dont think your suppose to put carb cleaner inside the IAC, theres seals inside that could get damaged.

[jonshonda]

Wrong^^ Cleaning it with carb cleaner is one of the only ways to clean it. It has worked countless times with positive results for the owner.

[TouringAccord]

Why did you do this?

Originally Posted by rollercosta123

subscribed

You can just click on Subscribe at the top right of the page and select to either Watch or Receive Email Notifications. You don't need to bump a thread to just subscribe to it.

[rollercosta123]

sorry. No reason to start complaining

[TouringAccord]

I'm not complaining, I'm informing.

[rollercosta123]

Finally!! It worked!!! Thanks!!!

[AJ06]

im gonna have to do this

[EvenStar]

need to know the abbraviations...

IACV?? FITV?? TB??

[TouringAccord]

IACV = Idle Air Control Valve

FITV = Fast Idle Thermo Valve

TB = Throttle Body

edit:
correct the IACV, thanks GhostAccord for catching that

[abxman]

I did just what you said to do. The problem went away. no more pulsating idle. The car runs real smooth, it's wierd adjusting to it. The only thing that i noticed is a random humming that comes on and off. it sounds like it's coming from the brake master cylinder area, but haven't check yet. Thanks hondadude, great directions and advice.

[BLUIZE256]

sticky. .
nice write up

[Grandhustleman86]

Originally Posted by abxman

I did just what you said to do. The problem went away. no more pulsating idle. The car runs real smooth, it's wierd adjusting to it. The only thing that i noticed is a random humming that comes on and off. it sounds like it's coming from the brake master cylinder area, but haven't check yet. Thanks hondadude, great directions and advice.

this write up is GREAT....i did this step by step on my 92 4dr dx and it worked like a charm....but i did not reset my ecu....any help on resetting it?

[JimBlake]

Originally Posted by Grandhustleman86

....any help on resetting it?

Disconnect your battery for a couple minutes. But first, find your radio anti-theft code...

Then, start the engine without touching the gas pedal. Let it idle to warm up completely without touching the gas pedal. After the radiator fan comes on, you're done.

[TouringAccord]

Originally Posted by JimBlake

Disconnect your battery for a couple minutes. But first, find your radio anti-theft code...

couldn't you just pull the ecu fuse? that way you don't have to worry about the radio.

[JimBlake]

Originally Posted by TouringAccord

couldn't you just pull the ecu fuse? that way you don't have to worry about the radio.

Yes.

But we've got a bunch of people in this thread, different year cars, etc. The ECU fuse isn't always the same fuse # in the same fuse box, and it doesn't always maintain the stereo security.

For '98-02 Accords, pull fuse #13 in the fusebox in the right end of the dashboard (near the door hinges).

[bamer36]

i love you you save me a lot of money

[Stevegunit16]

Im gonna try this for surezzzz!!!

[Shay91Racer]

wow this interesting... just bought my carb cleaner....

*I WILL POST FOR THE NONBELIEVERS* lol

[Shay91Racer]

hey but i have a question.... i was screwing the notch, as u mentioned, it turned about 4 times before being tight. However the question is this... when i took the brass plate of my FITV it was pretty much dirty inside it. what can i use to clean it?