Idle air control valve

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I have been search for this thing on the internet and under the hood for over and hour.

I have a 2003 chevy 5.3. I have a pic of the replacement part. Any help or a pic of it's location under the hood would be greatly appreciated.

[Scott K]

It is #1 in the picture

[Jeremy airjer W]

You'll also need to remove the plastic cover on top of the engine to see/replace it.

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Thanks for the pic and info. Is this the plastic plate that runs the full length on the top of the motor?

[Jeremy airjer W]

Yup, should have one screw holding it in place and I think it says vortec on it.

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I had that cover off. But still didn't see it. The picture of the location of the part #1 I can see but it doesn't look like the part I have a picture of on the Napa web site. Are the idle air control valve and the idle speed control two different things. The code I got off the truck was Man F VEH SPD Idle speed control and MAF OR UAF a CKT. My idle is slow 500 in park . I already cleaned the MAF with MAF spray changed the air filter Sea foamed the top half of the motor and cleaned the throttle body. The issue Im trying to fix is the low idle and rough idle. the worst issue I have is the truck going into limp mode with a engine reduced speed message on the dash. I not sure if I have to sep issues or what. I shut the truck off turn off everything electrical and off and running in 30 sec. The research I have done this problem could be many things and it sounds like the shops will throw many things at it before they find the issue. The only pattern I have found is it first goes into limp mode when the engine reaches normal running temp Not every time but most Your continued help is appreciated. I have my first baby is on the way next month just trying to save money. Everything I have done to the truck so far has never been done to it and should have. 183,000 on it.

[LightningBG]

Might be worth undoing the negative on the battery and letting it sit for 30 min or so. Then, if my assumption is correct, the engine will reset and go back into learning mode for that newly cleaned throttle body. Not sure if that will alleviate your problems though.

But, experts, please comment if this is an old wives tale.

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I was doing that every time it would stall. But later found out I didn't have to do this to get it running normal again . Just by turning off all electrical then restart in 30 sec works tell the next time it stalls.

[Scott K]

Since you are chasing a low idle issue, I would clean the throttle body really well. I would also remove the iac, and clean that as well, then relearning the idle, before replacing the iac.

[Jeremy airjer W]

Does this have Drive by wire? (TAC - Throttle actuator control). If there are no throttle cables attatched to the throttle body than you do not have an IAC you have a TAC. Basically it is an electric motor that controls both idle and throttle. The whole throttle body would be one assebly with one large connector with around 8 wires or so.

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Ding Ding Ding Ding we have a winner. I think you hit it on the head.No wonder I couldn't see it. When I cleaned the throttle body I didn't take it off. I just sprayed inside and used a tooth brush to remove the gunk. Wow for the gunk. Today the truck didn't stall on the way to work and the engine light turned off. I read it may take a couple days for the computer to reteach itself for the air fuel mixture. This is after cleaning the MAF and the throttle body.If it acts up agian I will take the TB off and clean it along with the sensor. The idle seemed ok today That may change now when it gets cold. I don't see much chg in the tach when I turn the AC on but do see a little when turning the steering wheel. Thanks for the help airjer. I will keep you posted

[LightningBG]

It wouldn't be a bad idea to take off the throttle body and clean it real good even if your problem has passed.

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I'm still having the same issue with the truck going into limp mode with a engine reduced speed massage on the dash. I pick up a new seal the throttle body is coming off this weekend. I did some more research and found that the positive cable is the one that needs to come off to reset the computer. I pulled the negative cable. The computer still thinks its running with a dirty system. So if I would have done this correct when I cleaned the TB without taking it off it might be running better.

Also note the seal I picked up is a rubber seal so I probably didn't need to get a new one. Just an FYI if someone is doing the TB cleaning. Also the TB spray will eat Tar so don't set the TB on the driveway while cleaning . Put it in a metal pan to clean it.

[Scott K]

I am not sure about GM, but on Fords if you open a ETC (throttle body) by hand, it wrecks it, and throws it out of calibration. On ETB systems, if you are going to clean them, clean the front side, and rear side without opening the throttle plate.

If the vehicle is going into limp mode it is more then likely a bad throttle body, because it seen a glitch in the reading, and it is locking it down, so you dont have unwanted acceleration (Toyota syndrome)

[LightningBG]

As far as I've heard. GM throttle bodies are commonly taken off, cleaned, worked by hand, etc, with no problems. I've done mine on my Envoy with no dire consequences.

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UPDATE I took off the old throttle body to clean it up. On the back side of the throttle body I found a small hole where the metal bends near the TPS that is inside the thottle body. Not sure if something let loose inside or what. I really don't think a rock or something could get up there and make the hole. I tried using stove pipe tape to seal it up but to much dirt had sucked in thru the hole and messed up the sensor. I replaced the throttle body $170 running great for a week. I will try to post pics of the hole. Thanks for all your help!