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Old 03-09-2011, 02:25 PM   #1
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Default Sick of high idle, please look at my idle settings

My car idles between 12-1400 RPM and I'm tired of it. Here is my current idle table. How do I get the idle to be closer to stock? Do I adjust the values in this table?
Sick of high idle, please look at my idle settings-idle.jpg
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Old 03-09-2011, 02:52 PM   #2
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I've found that while my car is warming up below 130 degrees, it likes a lot of WUE. Like 12.0 AFR. The car definitely lets you know when it is happy at idle.
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Old 03-09-2011, 03:01 PM   #3
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does the ecu do closed loop idle?
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Old 03-09-2011, 03:06 PM   #4
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It looks like he's electing not to...reasons unknown.
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Old 03-10-2011, 02:10 AM   #5
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Sick of high idle, please look at my idle settings-idle2.jpg
My .msq was always like this in idle settings ever since I went MS2. How do I get it to run closed loop? If I do run closed loop, will I ever see idle under 1000 RPM?
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Old 03-10-2011, 04:19 AM   #6
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That dropdown box, change it to PWM Closed loop....

Yes you can, but prepare to get frustrated qucikly and often whilst you tune the idle.
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Old 03-10-2011, 09:11 AM   #7
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Be prepared to read the MS3 closed loop idle tuning doc. Print it out and plan on 30min of idle tuning. Just do it. Don't try to tune a little here and a little there. It all works together. The msextra doc also gives a brief description of what each parameter does.
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Old 03-10-2011, 09:57 AM   #8
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I'm here right now: http://www.msextra.com/doc/ms3/Idle_Control.html
thanks for the info!
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Old 03-10-2011, 10:00 AM   #9
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yep. takes penitence and a lot of rereading to get it good.


if anything, to lower your idle speed, you'd just need to lower to PWM DC% numbers in the table you posted.

the lower the duty cycle, the lower the idle speed. Just think of it as the amount the valve is cracked open. 0 = closed 100 = open.

if you lower the numbers and the idle speed doesn't decrease, you need to turn the screw on the TB and let less air around the butterfly.
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Old 03-10-2011, 12:18 PM   #10
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Quote:
Originally Posted by Braineack View Post
yep. takes penitence and a lot of rereading to get it good.


if anything, to lower your idle speed, you'd just need to lower to PWM DC% numbers in the table you posted.

the lower the duty cycle, the lower the idle speed. Just think of it as the amount the valve is cracked open. 0 = closed 100 = open.

if you lower the numbers and the idle speed doesn't decrease, you need to turn the screw on the TB and let less air around the butterfly.
I wasn't sure there was an idle screw on the '99 TB, but since there is, keep the following in mind . . . there are three things that determine your idle speed:

1. Idle Air Control Valve Duty Cycle (already mentioned)
2. Idle Screw (already mentioned)
3. Spark advance in the idle region

That's it.
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Old 03-10-2011, 12:58 PM   #11
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I always looked at it like this...If the car idled fine with the stock ECU, then why would I even think about moving the idle screw? It's all ECU related. Like mentioned above, 1 and 3.
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Old 03-10-2011, 01:01 PM   #12
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Ooops. One other thing . . . :

4. Vacuum leaks

Are your sure everything is tight?
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Old 03-10-2011, 01:42 PM   #13
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Quote:
Originally Posted by thirdgen View Post
I always looked at it like this...If the car idled fine with the stock ECU, then why would I even think about moving the idle screw? It's all ECU related. Like mentioned above, 1 and 3.
so what happens if you reduce the idle valve's duty cycle?
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Old 03-10-2011, 01:43 PM   #14
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No vacuum leaks for me. I've been there and know what that's about. It happened when I swapped in my 460's the first time, it's pulling at least 21 inHG at idle now.
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Old 03-10-2011, 10:18 PM   #15
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I'm at work right now and I just thought of this. What if I warmed my car up and unplugged my idle valve wire? What if the idle doesn't change?
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Old 03-11-2011, 04:38 AM   #16
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Quote:
Originally Posted by thirdgen View Post
I'm at work right now and I just thought of this. What if I warmed my car up and unplugged my idle valve wire? What if the idle doesn't change?
1) Idle valve is fubar.
2) Idle output from MS is fubar.
3) Wiring between idle valve and MS is fuber.
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Old 03-11-2011, 05:40 AM   #17
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If you have a high idle, unplug your valve and the idle doesn't go any lower, then either the idle valve is faulty or you do in fact have a leak.
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Old 03-11-2011, 09:06 AM   #18
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What if, and I know this is a big if, you go hook up your laptop and adjust your idle settings?!
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Old 03-11-2011, 11:29 AM   #19
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If you can't control the idle speed with warmup only, switching to closed loop will do no good.

Make it so you can make the idle speed go up and down using the warmup-only table before moving any further.

Additionally, once you can do that, make sure you can drive around and have the idle return to a stable RPM without oscillation as well.

Ken
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Old 03-11-2011, 11:34 AM   #20
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Quote:
Originally Posted by Braineack View Post
What if, and I know this is a big if, you go hook up your laptop and adjust your idle settings?!
+1.

Play around with the idle valve test mode and get a feel for how it reacts to different pulse widths. Take a data log of a warmup from completely cold to when the thermostat opens, just idling without moving. That should give you a feel for what coolant temps cause you to idle high, and where you can pull down the pulse width values on your warmup curve.

Not all idle valves are the same. Figure out what yours likes.
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