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Old 05-08-2011, 06:32 PM   #1
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Default IAC Inflection point?

Has anyone ever experienced an inflection point in their IAC valve? That is, when using the idle valve test, in the lower % (say around 10) idle seems low, stays approximately in the 950 range until I get to 30%, then it lowers even more, in the 850 range, then as I increase the % the rpms increas as well.

Anyone ever experienced this? The reason I ask is because when in CL Idle mode, if the steps drop all the way down, my rpms are still high (1200ish) and the controller thinks it has no where to go since the steps are already low (20 steps, 7.8%).

The stock computer handles everything fine, which leads me to believe I have a setting wrong in my .msq. I attached my msq for reference.

The rpms at 20 steps still seem higher than the should be, which is probably what I am really trying to figure out.

Please let me know if you have any ideas. Thanks!
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File Type: msq 2011-05-07_15.55.51_timingANDveChanges_v.msq (78.9 KB, 37 views)
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Old 05-08-2011, 06:40 PM   #2
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The lowest you should go is 30%, below that the RPMs will actually start rising.
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Old 05-08-2011, 06:55 PM   #3
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That is exactly what I noticed. Phew. How do I prevent the MS from going so low? I set my Idle Valve Closed Duty to 30, and Open Duty to 65, but the MS will still allow the % duty and steps to go below the 30.
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Old 05-08-2011, 07:05 PM   #4
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If MS2, "Min duty for PID".
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Old 05-08-2011, 07:14 PM   #5
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Holy crap I'm dumb. I should have known that. Thanks for the dope slap. I need that once in a while.
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Old 05-08-2011, 07:40 PM   #6
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I do notice some 'looseness' to that. I have Both idle closed duty and min duty for PID set to 30.1, but I sometimes see duty drop to 29.5. Not too big an issue, but it does leave me scratching my head sometimes trying to figure out why it does that...
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