Still can't get car to idle right. rpms dropping to 500
05-09-2006, 09:03 PM
#1
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Still can't get car to idle right. rpms dropping to 500 k ive been playing with the Iac table in ls1 edit. it helped a bit, but im still getting some brutal idle problems. as i approach a light say i put the car into neutral it will drop to 450-500 rpm and i have to tap the throttle a couple times for it to pick back up, then it drops back down. it takes anywhere from 3-10 seconds for the computer to correct itself
anyways i was looking in the tables in ls1 edit, there is a table called "idle air"
in this there are 2 rows, "in gear" and "neutral" my in gear tab all seems normal, but the Neutral row every box is set to "0" so i dont know if this is contributing to the problem, if this was set to zero wouldnt that make the motor get no air at idle in neutral?
also, when it drops right down to 500 sometimes i can hear the airbox trying to suck a lot of air. it creates a loud enough vacuum for me to hear over my engine noise. not sure what this means?
someone suggested just drilling a hole in my TB but i really would like to avoid that if i can.
anyways i was looking in the tables in ls1 edit, there is a table called "idle air"
in this there are 2 rows, "in gear" and "neutral" my in gear tab all seems normal, but the Neutral row every box is set to "0" so i dont know if this is contributing to the problem, if this was set to zero wouldnt that make the motor get no air at idle in neutral?
also, when it drops right down to 500 sometimes i can hear the airbox trying to suck a lot of air. it creates a loud enough vacuum for me to hear over my engine noise. not sure what this means?
someone suggested just drilling a hole in my TB but i really would like to avoid that if i can.
05-09-2006, 09:28 PM
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If I remember right, stick shifts don't have idle air in the neutral row. Changing the idle air tables cant compensate for huge changes like a cam.
You can unbolt the the throttle blade and unscrew the throttle stop set screw and then place it on the top of the throttle body. This way you can adjust the throttle blade position with the throttle body on the engine. You adjust the throttle stop so you get enough air but don't open it small amounts. To much you won't have a low enough idle rpm or you will get a ses for the TPS voltage getting to high. Adjusting the throttle stop will eliminate the need to drill the throttle blade.
Do a search, there are plenty of detailed instructions on how to adjust for a cam. You can make minor adjustments with the idle air tables.
You can unbolt the the throttle blade and unscrew the throttle stop set screw and then place it on the top of the throttle body. This way you can adjust the throttle blade position with the throttle body on the engine. You adjust the throttle stop so you get enough air but don't open it small amounts. To much you won't have a low enough idle rpm or you will get a ses for the TPS voltage getting to high. Adjusting the throttle stop will eliminate the need to drill the throttle blade.
Do a search, there are plenty of detailed instructions on how to adjust for a cam. You can make minor adjustments with the idle air tables.
