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Closed loop idle too early?

Old 12-04-2015, 03:58 PM
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you all should be using adaptive timing as well. and battery votage idle % compensation.
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Old 12-04-2015, 03:58 PM
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I do. Though I'm just using basemap values. It helps a lot.
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Old 12-04-2015, 04:01 PM
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Thanks for the link, interesting 1st post about need 2 or higher for the PID Delay due to a code issue. I'll try bumping it up to 2 and see if that changes anything, I did notice it not kick in with very light throttle inputs.

I dunno if it's right, but I setup the setting in the lower right box so it would go into closed loop quickly when I let off the throttle.
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Old 12-04-2015, 04:03 PM
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Originally Posted by Braineack View Post
you all should be using adaptive timing as well. and battery votage idle % compensation.
Hmm, I now see the battery voltage idle% compensation, I'll mess with that.

What is the adaptive timing, just the Idle RPM Timing Correction? I do use that actually.
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Old 12-04-2015, 04:11 PM
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Aidan,

Try changing max decel load to a value closer to what you normally hit on overrun. I get down to 16 or so, so I've got it set at 18. This way, if for some reason CL idle activates while cruising, either PID disable RPMdot will kick it out, or the super low overrun map value will kill PID if RPMdot misses.

Also, set your TPS way negative if you need to, just try and get it so that you never start with positive TPS values. Everything else doesn't really matter, MS don't care if you are idling -2% TPS, because that's less than 1%.
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Old 12-04-2015, 04:24 PM
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I agree that it is a TPS issue.
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Old 12-04-2015, 05:25 PM
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Thanks guys.
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Old 12-04-2015, 10:33 PM
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I'm pretty sure it is a sticky throttle issue. When I slowly let off the gas it reads right around 5%. But if I blip the throttle and snap it shut then it goes back to 0.
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Old 12-04-2015, 11:18 PM
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Ok I'm stumped.

Slowly let out throttle. TPS stuck at 4%. Can't close it any further.

Blip throttle hard, TPS back at 0%.

This only happens when the engine is running. When it is off TPS always goes to 0%.
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Old 12-05-2015, 02:19 AM
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Originally Posted by aidandj View Post
Ok I'm stumped.

Slowly let out throttle. TPS stuck at 4%. Can't close it any further.

Blip throttle hard, TPS back at 0%.

This only happens when the engine is running. When it is off TPS always goes to 0%.
Easy. Does it idle at same RPM, or higher when TPS reads higher? I'm sure you can logically figure out if it's a sticking throttle or TPS sensor after asking yourself this question.
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Old 12-05-2015, 02:22 AM
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It idles higher because closed loop idle doesn't kick in when its stuck at 4%. But otherwise its the same. I pushed as hard as I could to close it and no change. Until I bliped the throttle.

I'm going to scope voltage tomorrow.
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Old 12-05-2015, 02:44 AM
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Originally Posted by aidandj View Post
It idles higher because closed loop idle doesn't kick in when its stuck at 4%. But otherwise its the same. I pushed as hard as I could to close it and no change. Until I bliped the throttle.

I'm going to scope voltage tomorrow.
Well yeah have idle control off to test.

But if you say it doesn't change then TPS is your problem.
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Old 12-05-2015, 10:12 AM
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try adjusting the TPS like i suggested. it could verywell be the tps needle thing is getting stuck and not the TB.

Last edited by Braineack; 12-05-2015 at 10:24 AM.
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Old 12-05-2015, 10:22 AM
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Originally Posted by Braineack View Post
try adjusting the TPS like i suggested.
Adjusting it how.
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Old 12-05-2015, 10:24 AM
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Originally Posted by aidandj View Post
Adjusting it how.
go find the damn post. hint post #8
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Old 12-05-2015, 10:44 AM
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Originally Posted by Braineack View Post
go find the damn post. hint post #8
its too early.
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Old 12-05-2015, 10:54 AM
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I'll try that. It's already adjuste d in the middle somewhat. About 360-900 on the ADC.

I turned lag off and there is barely any noise when just sitting.
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Old 12-05-2015, 01:54 PM
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I think there is a bug in the MS 3 code. It doesn't register negative rpm changes when looking at the PID disable.

Can someone confirm that it's different in ms2 code.

Test:

Set idle activation threshold to like 50% so you can get it to activate while driving.

Then get it to idle at part throttle. Set PID disable rpm dot to 300-400. Increase revs slower than your disable rpmdot and watch idle stay active. Increase faster than rpmdot and watch it disable. Now do the same with negative rpmsot. I did it by getting idle active while driving in a low gear, and then push in the clutch. My revs dropped and idle stayed on. Shouldn't it turn off?
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Old 12-05-2015, 03:02 PM
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Again I'm new to this, but why would you want closed loop to register negative RPM changes to disable it? If it did that, it would turn off closed loop if the RPMs drop and it tries to die on you- the opposite of what you want!
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Old 12-05-2015, 03:06 PM
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If it drops too fast I want it to exit closed loop and go back to my initial value table+dashpot. Because something bad is happening
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