Idle Control Screw on LS1
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Idle Control Screw on LS1 I would like to adjust the idle down on my LS1 a bit and not sure where the idle screw might be...??
This is my first LS1 I have had and not sure where it is...had LT1's and know those but do not know where it is on this motor..
Thanks
This is my first LS1 I have had and not sure where it is...had LT1's and know those but do not know where it is on this motor..
Thanks
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its called an Idle air control motor which is controlled by the computer. This is what controls the idle of a modern car.
Actually even newer cars that have an electronic throttle body dont even have one of these.
long story short, you need to change your computer calibration, which can be done.
Actually even newer cars that have an electronic throttle body dont even have one of these.
long story short, you need to change your computer calibration, which can be done.
YES there is a screw!!! if u look on to the throttle body cam, it should be where the cam rests at the idle position on the bottom, but as mentioned it was a pain to get to, i used a very little ratcheting wrench with a torx bit on it
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you can do that by the screw but its not as simple as turning the screw...theres a procedure that requires unhooking the tps and resetting the pcm"disconecting battery"...I dont care to type it all out do a search on idle adjust
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The way I understand it is if you want a lower idle you need to command it in the tune.
You have a target idle that the computer will try and maintain.
If you choke it off by closing the throttle, it will fight to get that air by adjusting the IAC.
So my guess is, if you close your throttle with the screw, your idle speed won't go down, the computer will just have to compensate with positive idle trims and your idle speed will stay the same.
That's what I think.
You have a target idle that the computer will try and maintain.
If you choke it off by closing the throttle, it will fight to get that air by adjusting the IAC.
So my guess is, if you close your throttle with the screw, your idle speed won't go down, the computer will just have to compensate with positive idle trims and your idle speed will stay the same.
That's what I think.
There is a TB set screw on the LS1 F-body throttle bodies and having it set correctly is an important part of the idle strategies for these cars. Here's a pic. Note how it's mounted upside down, so you have to adjust it from the bottom.
Last edited by DrkPhx; Dec 14, 2009 at 09:22 PM.
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From: Lexington, KY
Don't turn the screw in an attempt to adjust the idle speed! That's not what it's for. What you are actually doing is altering the idle airflow, which you don't want to do without tuning software. The idle speed is controlled by the computer. It may change slightly when you adjust the screw, but the computer will re-learn it back to where it thinks it is supposed to be. If you move the screw very much it will cause you problems and then you won't know where to put it back to.
