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Turbo Snail
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5,300 Posts
Discussion Starter #1 (Edited)
Your Idle Air Control Valve is located on the bottom side of your intake manifold. There is a white / grayish plug connected to it about 1 inch long.
Remove the electrical plug from it (Already removed in picture)


Remove your Coolant hoses
----- > You may want to put a bolt that threads into the line so you don't have a big mess. A 12mm head bolt should screw in no problem and keep coolant from leaking everywhere.
Using Needle nose, pliers, vise grips compress the hose clamp and move it towards the center of the hose.




Grab your pliers and twist the hose side to side to break the hoses free if they wont pull off


Grab a Offset Double Ended Screwdriver and locate the 4 phillips head screws that attach the IAC to the Throttle body.
------> This is very important to get the correct size for these screws. If you have the wrong size, you will strip the screws and you will have to drill / tap new holes. I found the double ended screw driver works great for this tight location under the throttle body. I am using the bigger of the two for this project




Break all 4 screws loose



Grab a regular phillips screw driver and remove all 4 screws the rest of the way





Grab your IAC by the plug side and lift up, removing the IAC from the throttle body.






Grab an All and pop the IAC Gasket out of the throttle body part way, and then grab it with your fingers and remove it the rest of the way (replace gasket) Notice that the gasket looks like a frog face :lol:








Now that your IAC is removed, and the gasket is replaced on the throttle body now its time to clean the IAC out!




To clean the IAC out, use any Sensor Safe cleaner. I will be using Seafoam, since I have a stock pile of it. hehehe



Spray the seafoam in the IAC and use a tooth brush or cloth and scrub the carbon deposits from the ports.


Make sure that you clean off where the IAC mounts to the Throttle body as well so that it has a better fitment.



If you really want to get in-depth with cleaning, you can remove the electrical plug from the IAC and clean it as well. This may help you clean out the IAC Better as well...


To remove that, use the double ended screw driver here as well to break the screws loose, and a phillips to remove them the rest of the way.





Now you can manually spin the inside divider left and right to full clean it.
Note that there will be spring pressure



Also, make sure to clean everything on this side very good as well. The cleaner everything is... the better!

now reinstall the screws for the IAC electrical connector, re-install IAC, and Presto! You've successfully cleaned your IAC fully!:thumbsup:


Addition ... Thanks to N/A sleeper for this information
Turns out that it IS adjustable as I had suspected by loosening the two small screws and doing some experimenting. First pic is where I started from...looks like it is close to midway between stops:



I first tried to turn it counterclockwise to its full CCW travel so it looked like this:



When I did this idle speed jumped to 2000 RPM and surged between about 1600 and 2000RPM with the computer (I guess) trying to compensate for too fast an idle. So I turned it the opposite way to full clockwise travel, and idle went to 750 RPM on the dot!

If you do the "remove-coolant-lines-to-IAC" mod then you will likely need to turn this adjustment plate FULLY CLOCKWISE for normal idle in colder weather - like so (I just inverted the picture here guys):



HOWEVER, I have no idea how it will idle in the summer months We shall have to wait and see
 

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抵抗は無駄で&#
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9,079 Posts
nice pictorial DIY :)

I vote sticky!

I think you could also energize IAC (for better cleaning, instead of removing electrical connector and turning manually) by connecting it to the battery ?
 

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Turbo Snail
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5,300 Posts
Discussion Starter #6 (Edited)
nice pictorial DIY :)

I vote sticky!

I think you could also energize IAC (for better cleaning, instead of removing electrical connector and turning manually) by connecting it to the battery ?

Yeah you could just jump the connectors on the AIC and have it turn automatically. Definately. I just noticed there was a lot of goop on it and wanted to get the entire thing clean :)


If you hook up these wires to a battery, it will cycle the IAC As well like Fenixus was speaking of

 

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Turbo Snail
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5,300 Posts
Discussion Starter #10
Yeah idle problems are linked with a stuck / bad iac.

Some people have it idle really high

Some people it idles really low when the AC is turned on.

For the surging

Might check the fuel pressure regulator. Could be too high or low pressure (or both), the regulator not doing its job.

Sometimes a pickup coil for the ignition system can have problems.

When it surges (car stationary) try shifting to Neutral and determine what happens.
 

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Turbo Snail
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5,300 Posts
Discussion Starter #12
Yeah idle problems are linked with a stuck / bad iac.

Some people have it idle really high

Some people it idles really low when the AC is turned on.

Intermittent stalling is also a sign, but could also be linked to other issues as well
 

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2001 Camry XLE 1MZ-FE
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1,620 Posts
Great job. And it really points out how squirting anything down the hole in the throttle body to clean the IACV is a half ass way to do it. You can see from the pics that you have to get in there and really scrub the crud out of there.

I don't know if the 5sfe IACV is any different than the 1MZ-FE, but when I took mine apart, I removed the entire sleeve with the vents cut in them. I thought that there was a stop on the sleeve because it would rotate so far and then stop. But it turns out that there was so much crud built up inside the body of the IACV it stopped the sleeve from turning. Once I remove the sleeve from the body, it could be cleaned up so the sleeve then spun freely and rotated 360 degrees in the valve body.


.
 

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イリジウム
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11,652 Posts
Excellent DIY. This is the proper way to clean the IACs. The silly magnetic motor design is just too weak and can stick with the lightest coat of carbon. Good work.

BTW, what coolant were you using? I see all that rusty residue.

(There was no Thank You button in message #1, so I clicked this one here. hehe)
 

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Turbo Snail
Joined
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5,300 Posts
Discussion Starter #16
Excellent DIY. This is the proper way to clean the IACs. The silly magnetic motor design is just too weak and can stick with the lightest coat of carbon. Good work.

BTW, what coolant were you using? I see all that rusty residue.

(There was no Thank You button in message #1, so I clicked this one here. hehe)

ehe , that IAC / TB is from my mystery motor (Salvage Yard). Thats why it looks like crap :D
 

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2001 Camry XLE 1MZ-FE
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1,620 Posts
I found some pics of when I cleaned my IACV and put something together showing what the valve looks like completely disassembled. Then you can see how the crud gets into to rotary valve and will clog it very easily considering that the cylinder is only moved by a magnetic motor.

On the V6 Calif spec valve there are two butterflys, at 180 degrees to each other. The larger one is to control all the air, as in the 4cyl and the smaller one is to control the engine vacuum. On an IACV with this setup, thats where the crud comes from. I don't know if you can see it in the lower left but there is a very small square hole that gets clogged with engine vapor crud, and cannot be cleaned without taking the valve completely apart.




.
 

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Registered
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263 Posts
I found some pics of when I cleaned my IACV and put something together showing what the valve looks like completely disassembled. Then you can see how the crud gets into to rotary valve and will clog it very easily considering that the cylinder is only moved by a magnetic motor.

On the V6 Calif spec valve there are two butterflys, at 180 degrees to each other. The larger one is to control all the air, as in the 4cyl and the smaller one is to control the engine vacuum. On an IACV with this setup, thats where the crud comes from. I don't know if you can see it in the lower left but there is a very small square hole that gets clogged with engine vapor crud, and cannot be cleaned without taking the valve completely apart.




.
Just making sure. The little square hole you circled in pink, that is on the other side of the throttle body right?
 
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