Adjusting idle
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From: Wheeling, WV
Adjusting idle
I've been searching the service manual high and low and can not find any information on adjusting the idle. I found info on how to check it, but not a procedure for adjustment.
I did see:
"NOTE: The idle speed is controlled automatically by the idle
air control system."
Beforing adjusting the BISS, do you have to ground a plug or anything like with the DSMs?
I did see:
"NOTE: The idle speed is controlled automatically by the idle
air control system."
Beforing adjusting the BISS, do you have to ground a plug or anything like with the DSMs?
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From: Wheeling, WV
Yes, there is the Base Idle Set Screw (BISS) on the t-body. Before you adjust the idle though, the IAC/ISC should be disconnected or disabled so it doesn't interfere with adjustment.
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I must be missing it casue I cannot find. Please can someone send me a pic. I have spent hours looks for this and am am stupid but I just need a pic and thats all. Please someone help me out. I will be forever greatful
Roger - This is KC form gvr4.org. Man, I am having idle issues as well and messing with tuning... 
From my searches, everyone says don't touch BISS, just mess with the rpm tables in Evoscan.
I may have a boost leak I guess, but last I checked, I didnt.
I do have a MIL.SPEC TB and wonder if my BISS does need adjusted...
Lastly, this SAS actuator to adjust BISS has been mentioned more than once. I need to know what thats all about

From my searches, everyone says don't touch BISS, just mess with the rpm tables in Evoscan.
I may have a boost leak I guess, but last I checked, I didnt.
I do have a MIL.SPEC TB and wonder if my BISS does need adjusted...
Lastly, this SAS actuator to adjust BISS has been mentioned more than once. I need to know what thats all about
Roger - here you go! 
Hope you have Evoscan 2.5 - This seems to be a popular way to set idle. I am about to try this tonight to see if my BISS is off...
https://www.evolutionm.net/forums/sh...t=SAS+actuator

Hope you have Evoscan 2.5 - This seems to be a popular way to set idle. I am about to try this tonight to see if my BISS is off...
https://www.evolutionm.net/forums/sh...t=SAS+actuator
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From: Wheeling, WV
Awesome, KC! Thanks.
I was having an idle issue and turned the screw. After a few moments it hit me like a ton of bricks... I forgot that you have to disable the ISC.
To make things even worse, my idle issue was cause from the PCV fresh air line that I forgot to reinstall after messing with the intake.
I was having an idle issue and turned the screw. After a few moments it hit me like a ton of bricks... I forgot that you have to disable the ISC.
To make things even worse, my idle issue was cause from the PCV fresh air line that I forgot to reinstall after messing with the intake.
no problem, ole buddy. Let me know how it works. I have some serious idle issues plauging the car and me. Not sure if its the cam degree off, boost leak, bad 02 sensor up front etc etc...AAGH!


