How to clean your IAC (Idle Air Controller) valve

Chris

Chris

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If you're experiencing idle issues on your Jeep Wrangler TJ the most likely culprit (and the first thing you should check) is your IAC (Idle Air Controller). Often times the IAC gets very gunked up causing the Jeep to idle improperly. A simple cleaning is usually all it takes to get it running as good as new.

If you end up needing to replace your IAC valve (they do fail on occasion), you can find the part numbers (and the links to purchase them on Amazon) below:

2005-2006 IAC Valve (Part # 4861552AC)
1997-2004 IAC Valve (Part # 4874373AB)

There is no need at all to remove the throttle body to clean the IAC. This is probably one of the easiest and cheapest things you can do.

Below you'll see a diagram of the top of your throttle body with the IAC sensor labeled.

1_v2.jpg


Take your IAC off (it's held on by two small torx screws). Clean it with your throttle body cleaner, this is what it will look like before and after.

2.jpeg


3.jpeg


Then take off the IAC housing and both sides (house and throttle body). clean that too. before and after...

4.jpeg


5.jpeg


6.jpeg


Put it all back together and you're good to go. Very, very simple. It doesn't get any easier than this!
 
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Thank You, Sir., and now I will have to investigate this as well- as time allows. Could be a day to a month or so but it is so awesome to get fixes to problems so fast here. When I do get to it I will post the results.
 
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Neskie Crawler said:
Thank You, Sir., and now I will have to investigate this as well- as time allows. Could be a day to a month or so but it is so awesome to get fixes to problems so fast here. When I do get to it I will post the results.
Click to expand...

Sounds good. Looking forward to seeing if that fixes the issue or not!
 
An update on this and a huge thanks to all involved; this was an issue I posted in the general forum I think- my tj would idle high enough to climb a steep hill off road,but only after the motor was hot. Engage the clutch and get high revs till the motor got air-cooled and the idle returned to normal. I finally took the iac valve off today and it was gunked up just as the above "before" pic. I cleaned it with gum cutter and got the parts in the assembly moving again, re-assembled and took her for a test ride. No more high idle issue when the motor is up to temp. A fairly easy repair and no cost involved. Thanks again!:)
 
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Well, I've had this issue off and on for awhile. I've ordered a new IAC and TPS sensor, but then I saw this write up. I took everything apart and cleaned everything per these instructions, but I still have the issue. Hopefully when the new sensor gets here, that'll fix it.

Just in case, is there anything else it could be?
 
Last edited:
Chris said:
If you're experiencing idle issues on your Jeep Wrangler TJ the most likely culprit (and the first thing you should check) is your IAC (Idle Air Controller). Often times the IAC gets very gunked up causing the Jeep to idle improperly. A simple cleaning is usually all it takes to get it running as good as new.

Put it all back together and you're good to go. Very, very simple. It doesn't get any easier than this!
Click to expand...

Thanks for the heads up chris. Fun little Sunday project. Didn't really notice poor idle, but this baby is mighty gunked up.

99bf8f86193cab6e65d259b137429ce8.jpg



Sent from my iPhone using Tapatalk
 
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Can you clean this with anything else besides Throttle Body Cleaner?
 
Removed and cleaned the IAC module to-day ...... used some superfine steel wool to gently clean the seat / plunger.
Had some 'carburetor cleaner' and used that. It was easier to gently lift the throttle body .... then remove the IAC module.
Re-install, and torque the TB mounting bolts to 90 inch/lbs .....

I've been chasing a surging problem with my (new to me) '04 TJ ...... 4.0L / 5speed.
This cleaning, and new plugs are just part of the process of elimination .....
Not sure where to go from here.
Suggestions most welcome.
Thanks,
HL
 
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Head Lice said:
Removed and cleaned the IAC module to-day ...... used some superfine steel wool to gently clean the seat / plunger.
Had some 'carburetor cleaner' and used that. It was easier to gently lift the throttle body .... then remove the IAC module.
Re-install, and torque the TB mounting bolts to 90 inch/lbs .....

I've been chasing a surging problem with my (new to me) '04 TJ ...... 4.0L / 5speed.
This cleaning, and new plugs are just part of the process of elimination .....
Not sure where to go from here.
Suggestions most welcome.
Thanks,
HL
Click to expand...

No check engine light?
 
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