Correct idle speed, LT1
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Joined: Jan 2003
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From: harvest al
Correct idle speed, LT1
Can someone tell me what the correct idle speed is for an LT1? Mine is a 95 LT1, 6M. Right now it idles at about 900 RPM which seems a little high to me. Also, the idle speed adjustment screw seems to be frozen or maybe has lock-tite on it. Any advice on getting it to move?
Thanks, John
Thanks, John
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From: More cowbell...
St. Jude Donor '04
Re: Correct idle speed, LT1 (sundbergjc)
If I recall correctly, my stock LT1 idled at around 500-600 when in gear. Are you using the tach as your RPM measurement, or a computer hooked up to the car? The stock vette tach's are notorious for being inaccurate.
As for the minimum idle screw- did you take out the plug that is behind it, and use a torx T-20 to move it?? Or were you just trying to turn it with a pliers? If the latter, you need to dig out the plug that is behind the screw..
Edit- this really wont bring down your idle speed though- the idle is actually controlled by the IAC, which is controlled by your computer. If your idle is too high, my guess is that the IAC is stuck open, and needs a good cleaning. Take off the throttle body, and clean it real well (make sure you pay close attention to the IAC- get all the black buildup off of it, but DONT use carb cleaner. Then re-install, and see if it helps.
[Modified by MarkLT1, 9:32 AM 4/16/2003]
As for the minimum idle screw- did you take out the plug that is behind it, and use a torx T-20 to move it?? Or were you just trying to turn it with a pliers? If the latter, you need to dig out the plug that is behind the screw..
Edit- this really wont bring down your idle speed though- the idle is actually controlled by the IAC, which is controlled by your computer. If your idle is too high, my guess is that the IAC is stuck open, and needs a good cleaning. Take off the throttle body, and clean it real well (make sure you pay close attention to the IAC- get all the black buildup off of it, but DONT use carb cleaner. Then re-install, and see if it helps.
[Modified by MarkLT1, 9:32 AM 4/16/2003]
Thread Starter
Instructor
Joined: Jan 2003
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From: harvest al
Re: Correct idle speed, LT1 (MarkLT1)
So far just looking at the on board tach. Did remove that plug but didn't realize it was a torx (the head is recessed in the housing where you can't really see it). Will try that. Thanks
Le Mans Master
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From: More cowbell...
St. Jude Donor '04
Re: Correct idle speed, LT1 (sundbergjc)
If you havent cleaned the throttle body yet, try that first..
The reason the plug is there in the first place, is you really arent supposed to adjust that screw, unless you have done some serious mods, and need to bump your idle way up (and have reprogrammed the computer to do so).
The reason the plug is there in the first place, is you really arent supposed to adjust that screw, unless you have done some serious mods, and need to bump your idle way up (and have reprogrammed the computer to do so).
Racer
Joined: Jan 2003
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From: Sumter South Carolina
Re: Correct idle speed, LT1 (MarkLT1)
He's right, the idle speed is controlled by the IAC/computer. By adjusting the screw, the computer would recompute the idle speed, and it wouldn't change. However, you want to make sure that the throttle plate is stopping on the screw, if it isn't it will grove your throttle body butterfly, which is bad.
Le Mans Master
Joined: Sep 2001
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From: More cowbell...
St. Jude Donor '04
Re: Correct idle speed, LT1 (sundbergjc)
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