Idle Air Control Valve Part Recommendations

[reganz18750]

I am pretty sure I need to clean my idle air control valve and thinking I should just replace it while I have it off.
My question is there is a large price difference in the cost between the Mopar 4874373AB for $100+/- and the other ones for $10-$20 bucks. Curious if anyone has used the cheap ones? I will probably just get the Mopar but also noticed the link in the IAC cleaning guide says Mopar but the reviews show a Crown part?

 

[Jerry Bransford]

Don't replace the IAC yet, simply cleaning it normally restores it back to 100% good operating condition. But where such parts like that and sensors are concerned, I always recommend the OEM part... aftermarket sensors are a crapshoot. But again, just clean it and it'll likely be fine.

In fact, you don't even normally have to remove the IAC to clean it. With a can of throttle body in hand, start the engine after removing the air intake tube from the throttle body. With the engine at idle rpms (don't raise the rpms up from idle), spray the cleaner into the throttle body opening where the IAC will suck the cleaner in through itself. The IAC will flood/fill up with the cleaner which will stall the engine which is fine and as it should be. Restart the engine and do it again until you've gotten at least 1/3 of the can through the IAC. That will also clean the orifice (hole) in the throttle body the IAC's plunger fits into and moves in/out inside of.

Don't waste your time & money on a new IAC until you've cleaned the IAC and learned it didn't fix the problem which is unlikely.

You can see the slot (idle air control passage inlet) in the below drawing the IAC draws its air through. That's the slot the IAC will suck the cleaner in through when the engine is running. The IAC will no longer be drawing air and pulling the cleaner in through itself if you raise the engine rpms up off idle so don't do that. Once you've used 1/3 of the can to clean the IAC, then you can raise the engine rpms and empty the can to clean the rest of the inside of the throttle body.

 

[MaloStapalo]

It feels weird spraying fluid into the throttle body but Jerry is 100% correct. This helped me solve my dirty IAC

 

[1Blacktj]

Don't replace the IAC yet, simply cleaning it normally restores it back to 100% good operating condition. But where such parts like that and sensors are concerned, I always recommend the OEM part... aftermarket sensors are a crapshoot. But again, just clean it and it'll likely be fine.

In fact, you don't even normally have to remove the IAC to clean it. With a can of throttle body in hand, start the engine after removing the air intake tube from the throttle body. With the engine at idle rpms (don't raise the rpms up from idle), spray the cleaner into the throttle body opening where the IAC will suck the cleaner in through itself. The IAC will flood/fill up with the cleaner which will stall the engine which is fine and as it should be. Restart the engine and do it again until you've gotten at least 1/3 of the can through the IAC. That will also clean the orifice (hole) in the throttle body the IAC's plunger fits into and moves in/out inside of.

Don't waste your time & money on a new IAC until you've cleaned the IAC and learned it didn't fix the problem which is unlikely.

You can see the slot (idle air control passage inlet) in the below drawing the IAC draws its air through. That's the slot the IAC will suck the cleaner in through when the engine is running. The IAC will no longer be drawing air and pulling the cleaner in through itself if you raise the engine rpms up off idle so don't do that. Once you've used 1/3 of the can to clean the IAC, then you can raise the engine rpms and empty the can to clean the rest of the inside of the throttle body.

View attachment 56470

what cleaner are you using?

 

[Jerry Bransford]

what cleaner are you using?

Any aerosol that says throttle body cleaner, they're all fine.

 

[Hawaiian TJ]

Aloha from Hawaii,
I own a 2003 TJ, my IAC problem has to do with the connector not having a solid connection. is it supposed to securely fasten to the sensor like the other sensors do, because I'm able to pull the connector off w/out push/pulling any locking tab...so I'm thinking that because its not securely fastened on, the inner prongs are not connected causing the P505 to come on, which is possibly causing my surging issues.

 

[SteamboatJPN]

Don't replace the IAC yet, simply cleaning it normally restores it back to 100% good operating condition. But where such parts like that and sensors are concerned, I always recommend the OEM part... aftermarket sensors are a crapshoot. But again, just clean it and it'll likely be fine.

In fact, you don't even normally have to remove the IAC to clean it. With a can of throttle body in hand, start the engine after removing the air intake tube from the throttle body. With the engine at idle rpms (don't raise the rpms up from idle), spray the cleaner into the throttle body opening where the IAC will suck the cleaner in through itself. The IAC will flood/fill up with the cleaner which will stall the engine which is fine and as it should be. Restart the engine and do it again until you've gotten at least 1/3 of the can through the IAC. That will also clean the orifice (hole) in the throttle body the IAC's plunger fits into and moves in/out inside of.

Don't waste your time & money on a new IAC until you've cleaned the IAC and learned it didn't fix the problem which is unlikely.

You can see the slot (idle air control passage inlet) in the below drawing the IAC draws its air through. That's the slot the IAC will suck the cleaner in through when the engine is running. The IAC will no longer be drawing air and pulling the cleaner in through itself if you raise the engine rpms up off idle so don't do that. Once you've used 1/3 of the can to clean the IAC, then you can raise the engine rpms and empty the can to clean the rest of the inside of the throttle body.

View attachment 56470

Jerry - one question. Is this method preferred over complete disassembly and clean? In your opinion, does the dirty residue harm the engine at all? I have the time to do either, so just wanted to check!

 

[Jerry Bransford]

Jerry - one question. Is this method preferred over complete disassembly and clean? In your opinion, does the dirty residue harm the engine at all? I have the time to do either, so just wanted to check!

I believe this method is better. It cleans the IAC out to stop idle problems caused by insufficient airflow through a dirty obstructed IAC. Spraying it into the throttle body while the engine is running gets the cleaner through 100% of the IAC system.

The engine has to get ALL of its air through the IAC when it's at idle rpms. Any obstruction in the IAC system will affect the idle quality.

 

[SteamboatJPN]

@Jerry Bransford - wanted to send an update! Cleaning the IAC as you stated seemed to fix the problem entirely!! I was thrilled to see it and hope it remains solved! I started it a few times after sitting for a little over 24 hours. Thanks all.

 

[Tjrubicon]

@Jerry Bransford - I had the odd whistling noise coming from my engine bay, mostly at idle to little throttle. I used Jerry’s cleaning method and it completely fixed the issue. I believe the engine is now running better than ever. Thanks for the posted advice.

 

[1Salty Dawg]

I did all the cleaning and I still idle at just over 1k and P505 CEL sends its warm glowing color at me every time I start it.

 

[Jerry Bransford]

I did all the cleaning and I still idle at just over 1k and P505 CEL sends its warm glowing color at me every time I start it.

How did you clean it? Did you remove the IAC to clean it or did you spray TB cleaner into the throttle body at idle rpms while the engine was running?

 

[1Salty Dawg]

How did you clean it? Did you remove the IAC to clean it or did you spray TB cleaner into the throttle body at idle rpms while the engine was running?

engine on, quick shots of throttle body cleaner, stalled out once, started back up, few more quick shots (about 3 seconds per shot) no change in anything.

 

[SamBone02X]

I did all the cleaning and I still idle at just over 1k and P505 CEL sends its warm glowing color at me every time I start it.

My 02 was idling a 1K when first started and idled somewhat rough (different issue), but if it idles a 1K and is slow to accelerate as well as if your transmission is slow to shift, replace your Throttle position sensor. It fixed my high idle issue as well as the other issues mentioned. Good Luck.

 

[1Salty Dawg]

My 02 was idling a 1K when first started and idled somewhat rough (different issue), but if it idles a 1K and is slow to accelerate as well as if your transmission is slow to shift, replace your Throttle position sensor. It fixed my high idle issue as well as the other issues mentioned. Good Luck.

Actually acceleration is pretty responsive.

 

[1Salty Dawg]

Guess I'll recheck for vacuum leaks. I don't get it.

 

[Jerry Bransford]

Guess I'll recheck for vacuum leaks. I don't get it.

With the engine running spray all the vacuum line connections, manifolds, etc. with something like a throttle body cleaner, brake cleaner, starting fluid, etc.. If the spray gets into the engine through a leak you'll hear the rpms surge.

 

[1Salty Dawg]

So right where I have the pencil pointed to when I hit it with TB cleaner the rpm's fluctuate noticeably.

 

[Jerry Bransford]

That location wears where the shaft passes through and causes vacuum leaks. I'm not aware of an effective way to fix the leak other than to replace the throttle body.

 

[1Salty Dawg]

That location wears where the shaft passes through and causes vacuum leaks. I'm not aware of an effective way to fix the leak other than to replace the throttle body.

Dang it Jerry I was afraid you would say that but thanks for your help. It must be enough to make the CEL come on but not enough to affect the Jeeps performance.