mjwalfredo

So about 2 weeks ago, I cleaned the Idle Air Control Valve with some carb cleaner and a toothbrush because the truck had a very low idle speed when warm (500rpms). Now it idles relatively low, ~800rpm , on a cold start and it idles high, ~1400rpm, when warmed up in neutral. I tried disconnecting the battery to reset the computer but that did no good. Could this be a vacuum leak? The motor does have 200k mi on it with mostly original hoses. Anything else come to mind?

mjwalfredo

Nobody? Well my truck has been idling at ~1200 rpm when warm for a while now. Is this something I need to get fixed right away? The only downside I can see is that it will be using more gas.

MTL_4runner

Please explain what exactly did you do when you cleaned the IAC.

mjwalfredo

What I did to clean the IAC:

1. Removed throttle body.
2. Removed the 4 screws attaching the IAC to the throttle body.
3. Removed the 2 screws for the IAC cover.
4. Cleaned the valve with Carb cleaner and a toothbrush. Tried not to touch the magnets with any cleaner. I did wipe them a clean cloth.
5. Sealed the cover with permatex right stuff and attempted to put everything back together very carefully so as not to get the right stuff on any magnet/sensors.

Maybe I used too much Permatex?

Now when the motor is warm, the idle is HIGH. When you cut off the motor, it does not come to an abrupt stop anymore. It comes to a stop slower and makes a cool growling sound like when you cut off a fourwheeler with the key rather than the on/off switch.
When you start the motor up when it's cold, it feels like it stumbles for half a second but idles just fine even though it is much lower than the normal fast idle.

It's not possible to put the IAC back on upside down/backwards is it?

mjwalfredo

Oops double posted.

mjwalfredo

This must be something out of the ordinary here... I think I am going to try switching out my throttle body with the the one off my roommate's '98 4Runner. Hopefully they are the same. That will at least narrow it down down to something on the throttle body (probably IAC). If it is trashed, I hope they are not too expensive...

MTL_4runner

Try that and see if it helps. If it idles normally with the other throttle body, then more than likely you just put it back together wrong. When you take apart the IAC and remove just the magnetic coil side, then you should be fine, but if you remove the other side with the spring and don't get it back together properly, it will do exactly what you are talking about (high idle, etc). Remove the IAC on yours and compare it to the one on the good throttle body to be sure the valve at rest is in the exact same place. If not, it's not together correctly. Also post a pic of the good IAC if you can because it will be very helpful to others who might experience the same problem in the future.

5-spd for life!

I think that when you put the IAC valve back in you made a big mistake. The little cover that has the magnets in it is not supposed to be removed hints the red markings on it from hte factory, but your in luck because I did it anyway and got mine working again. Just take it back apart and make sure that the magnets are in the right spot with the right tension, but you used the right stuff so you may have completely screwed yourself! That stuff is very permanent!

MTL_4runner

Did you take apart the coil side, spring side or both?

mjwalfredo

I am not sure if I took apart the coil or spring side, LOL.

Basically, if you look at the pic below, I removed those two screws and pulled that plastic piece off. In retrospect, it looks like I did not even need to do that and I probably F'd something up when I took that guy off. I tried not to spray any cleaner on the junk inside that plastic piece, i just wiped the coil and magnets (I guess, not really sure what is inside there) with a Q-tip.

Oh, and I used the rite stuff to seal the plastic piece back. I did not use it to replace the rubber o-ring....

MTL_4runner

The green part in the pic is the coil/solenoid side the opposite end is the return spring side.
Did you only take apart the green side? or did you open the opposite end too?
Both ends are only held on by two screws which is why I ask.

You want to fix the one you have because a new IAC ain't cheap.
It's P/N 22270-62050 and they're about $230 new from the dealer.

mjwalfredo

Yeah, I only took apart the green end. If I get some time on Sunday I am going to pull it all apart again, double check everything and put it back together. We'll see what happens then.

MTL_4runner

Swap the throttle bodies with your friend and let us know how you make out.

MTL_4runner

I recently solved my own IAC issue and thought you might want to have a look:
http://www.ultimateyota.com/smf/inde...30618#msg30618

mjwalfredo

Jamie,

Thanks for the good info in the link. It is great to hear about someone having and resolving similar issues. I'll have to wait until next week before I can swap the throttle bodies and then possibly dig into the unit since my girlfriend needs to borrow the 4Runner for a trip and is leaving tomorrow morning. I will be sure to let ya'll know how it goes once I start on it.

mjwalfredo

My troubles are over tonight thank the lord. It turns out the "Right Stuff" I used to seal the green housing to the valve had gotten onto the magnet/sensors. I tried taking pics but it is tough with a broken screen on your digital camera. I used some gasket remover and some electrical contact cleaner to remove the sticky right stuff and clean everything up. She idles and drives beautifully now.

If I had to guess what was happening, I would say the right stuff was keeping the valve from opening when the motor was cold. Once the motor warmed up and then in turn the right stuff, it would stretch out and become gummy. The valve probably opened up and would be slow to close with the gummy substance attached to it.

Thanks for all the help.

MTL_4runner

Good to know you got yours fixed too!

ubermoto

Hey MTL, just read your post over on ultimateyota... When you bench tested your IAC, how far did it close? When I tested mine, it didn't quite close all the way - maybe 1/8" of gap... Is this adjustable? Do you mind explaining how? I think this may be the reason for my high idle... I don't want to have to buy a new one if I don't have to...

https://www.yotatech.com/forums/f2/3...h-idle-198330/

Cheers,

Jeremy