IAC Removal, L98
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IAC Removal, L98
I have a '87 L98 that I am trying to remove the IAC. Is there a special tool to unscrew it? The way it's located, it is almost impossible to get a conventional socket or wrench on. An tricks? Thanks in advance for any replies.
Burning Brakes
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Burning Brakes
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I used an adjustable wrench to remove mine, no hex screws. On other cars I've seen them held in by two hex screws but not a Vette his year.
Burning Brakes
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a wrench fits right on it, about a half a turn and its loose
Team Owner
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From: Summerland B.C. Canada
There is not much room for a large open end to fit on hex, needle nose vise grips work fine for me.
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Burning Brakes
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To me, Vise-Grips are an emergency tool and I only use them for something that is frozen, my adjustable fit fine. Vise-Grips scratch and damage parts, why not just use the right tool? There is NO WAY a vise-grip is not gonna scratch and chew-up the hex, I just wouldn't do it. "GRIP" is the key word in that equation, why do it?
Team Owner
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From: Summerland B.C. Canada
To me, Vise-Grips are an emergency tool and I only use them for something that is frozen, my adjustable fit fine. Vise-Grips scratch and damage parts, why not just use the right tool? There is NO WAY a vise-grip is not gonna scratch and chew-up the hex, I just wouldn't do it. "GRIP" is the key word in that equation, why do it?
Please post a pic with your adjustable wrench on the IAC.
Burning Brakes
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I'm not gonna take it apart to prove it, I've had it out three times, each time the same way. I think you have a beautiful car and you give great and informative advice here, but I was just going through the forum with two master mechanics at my house and both agreed with there being no reason to Vise-Grip that part. If it works, than thats fine, but using any of my Vise-Grips for that job would never enter my mind. I mean if I had to, I'd try and get it out with a salad fork if that was all I had at my disposal, but I have the right tools for the job. I was thinking of cutting open a thin-walled box wrench just for that job but I busted out my large adjustable wrench and at the right position, it fit right on. I mean it's no big deal, but I just don't like chewing up or marring the surface of something I'm not planning on throwing away. It's like using a strap-wrench on chrome plumbing fixtures, some people will use a Channel-Loc which will work, but why leave teeth marks?
Burning Brakes
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I get the impression your talking about removing it without removing the throttle body, which I wouldn't do because I wouldn't want to break anything. It takes 2 minutes to remove the throttle body and do it like a gentleman
Burning Brakes
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I have sockets I can line up to the moon, adjustable is still easier. I don't remember there being enough room for a socket, fittings were to close if I remember. I can get my IAC out as fast as I can reassemble a 1911 45ACP, thats fast enough for me.
Burning Brakes
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I just remembered that I had an extra throttle body and IAC and took it out to look at it and take a picture that I'll put in "My garage" a little later. I remembered right, a socket does NOT fit unless you notch the body housing, any socket I have is too thick to slip on it and there is plenty of room for the wrench once the body is disconnected and facing up towards you. I've never seen such a big socket thin walled enough to fit in this space unless something was changed or trimmed, there is just not enough room. Now if I shaved the housing a little, maybe a 16th or so, then a socket would slip over it. I know I'm gonna hear from nay'sayers, but I got it in my hand right now and it is what it is, PERIOD!!
Burning Brakes
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I just posted the pic to "My Garage and am holding the body the way I would under the hood. I remove the cables, then the vacuum lines, then the body, then the plug. I don't remove the coolant lines, I turn it up to that position and "CRACK" a half turn with the wrench and it screws out, nothing abusive at all and no scratches because I'm sick that way
Team Owner
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From: Summerland B.C. Canada
Putting a crescent wrench on a IAC that is not on the car is easy.
Show me on your car with the AIR valves and all that other crap, is in the way.
Burning Brakes
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The OP was looking for suggestions as it is a pain to get a wrench on it, as stated. I offered an option that worked for me.
Putting a crescent wrench on a IAC that is not on the car is easy.
Show me on your car with the AIR valves and all that other crap, is in the way.
Putting a crescent wrench on a IAC that is not on the car is easy.
Show me on your car with the AIR valves and all that other crap, is in the way.
Smarter not harder, when the body is off you can service it and clean everything with spray. Why in Gods name would anyone want to attempt taking that valve out while everything is mounted? I wouldn't even think about it.
Last edited by caddyboy84; May 1, 2012 at 06:44 PM.
Team Owner
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From: Summerland B.C. Canada
Exactly, EASY. There is no reason to remove that valve without removing the throttle body first , it makes no sense and I would never suggest to any one to do so. My first response was to remove it, if I wanted to torture myself for no reason, I'd hit myself on the hand with a hammer every morning when I wake up Smarter not harder, when the body is off you can service it and clean everything with spray. Why in Gods name would anyone want to attempt taking that valve out while everything is mounted? I wouldn't even think about it.
Smarter not harder, when the body is off you can service it and clean everything with spray. Why in Gods name would anyone want to attempt taking that valve out while everything is mounted? I wouldn't even think about it.The reason I did, is because my TB had already been cleaned and serviced, but later decided to replace the IAC. If I can take a shortcut and do something in 1/4 of the time, I'll do it, just like replacing a heater core. FSM would have you there for hours and hours, when it can be done in 2 hours with short cuts. Time is money, honey.
Burning Brakes
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The OP asked how to remove it without removing the TB, I gave him an answer. I'm sure he is smart enough to see that removing the TB is the best way, but not the only way.
The reason I did, is because my TB had already been cleaned and serviced, but later decided to replace the IAC. If I can take a shortcut and do something in 1/4 of the time, I'll do it, just like replacing a heater core. FSM would have you there for hours and hours, when it can be done in 2 hours with short cuts. Time is money, honey.
The reason I did, is because my TB had already been cleaned and serviced, but later decided to replace the IAC. If I can take a shortcut and do something in 1/4 of the time, I'll do it, just like replacing a heater core. FSM would have you there for hours and hours, when it can be done in 2 hours with short cuts. Time is money, honey.
I'm starting that job tomorrow with removing the radiator, reversing my fans and adding a tranny cooler then THE CORE
. I gotta "Butt Heads" with ya here He never said "Without removing" the throttle body. I'm one for cutting corners, but with limits, I'd hate to see a new thread about "OMG I broke my throttle body cooling nipple!!, or, "I cracked my plastic IAC plug housing"!! I think I'm pretty good and I thought about trying to remove that thing on the plenum but the more I studied it and put this tool up to it and that tool up to it, I said CRAP!! I could've had this out already in the time it took me to try and save time. I would think that doing it your way would not allow enough leverage to properly tighten it down without chewing it up. Honestly though, if someone is asking about this issue, is it plausable to think that they would be able to do it that way? Your way is a trial and error style (which I understand) but shouldn't be suggested for the novice.