# Short Term Trim Correction

**URL:** <https://community.ecumaster.com/t/short-term-trim-correction/2731>\
**Category:** EMU BLACK / CLASSIC\
**Created:** [November 10, 2024, 7:24am UTC](https://community.ecumaster.com/t/short-term-trim-correction/2731 "2024-11-10T07:24:13Z")\
**Posts on this page:** 13\
**Page:** 1

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**Author:** ![xsd](https://avatars.discourse-cdn.com/v4/letter/x/b5e925/32.png) [@xsd](https://community.ecumaster.com/u/xsd)\
**Post date:** [November 10, 2024, 7:24am UTC](https://community.ecumaster.com/t/short-term-trim-correction/2731/1 "2024-11-10T07:24:14Z")

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Hi  
Have sometimes under WOT Conditions that the Fuel Short Trim is not responsive.

As Example Lambda Target 0.77 and I have 0.719 → Short Term Trim 100%

So my Question is where should I look first…Lambda Delay or P and I Correction?

 ![20241110_082348](https://europe1.discourse-cdn.com/flex013/uploads/ecumaster/original/2X/7/7aa3e72655020d3f628e844ebb5f4638ca7cfa1d.jpeg)  
 ![20241110_082339](https://europe1.discourse-cdn.com/flex013/uploads/ecumaster/original/2X/e/e50d3f417174d1be14ab90085b8ec6f1fe9c3629.jpeg)

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**Author:** ![derUltraTT](https://avatars.discourse-cdn.com/v4/letter/d/ba8739/32.png) [@derUltraTT](https://community.ecumaster.com/u/derUltraTT)\
**Post date:** [November 10, 2024, 12:41pm UTC](https://community.ecumaster.com/t/short-term-trim-correction/2731/2 "2024-11-10T12:41:34Z")

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First u set lam delays correctly by taking different exhaust flow points, steady state and then digitally change lam target without shortermtrim active and measure the lam responses and fill the table.  
Then u tune P portion…then I portion like in every other PID.  
Increase the values till it starts to osciallate. This is then the max value u should set.

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**Author:** ![kimbaku](https://avatars.discourse-cdn.com/v4/letter/k/8edcca/32.png) [@kimbaku](https://community.ecumaster.com/u/kimbaku)\
**Post date:** [November 10, 2024, 2:28pm UTC](https://community.ecumaster.com/t/short-term-trim-correction/2731/3 "2024-11-10T14:28:18Z")

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You can use debug - pid - shortTrim log a file and open Debug PID channels for each of them.Then you can see exaclty how the controller acts

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**Author:** ![xsd](https://avatars.discourse-cdn.com/v4/letter/x/b5e925/32.png) [@xsd](https://community.ecumaster.com/u/xsd)\
**Post date:** [November 10, 2024, 6:21pm UTC](https://community.ecumaster.com/t/short-term-trim-correction/2731/4 "2024-11-10T18:21:47Z")

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Good Points will try booth

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<div class="post-metadata">

**Author:** ![xsd](https://avatars.discourse-cdn.com/v4/letter/x/b5e925/32.png) [@xsd](https://community.ecumaster.com/u/xsd)\
**Post date:** [November 10, 2024, 6:42pm UTC](https://community.ecumaster.com/t/short-term-trim-correction/2731/5 "2024-11-10T18:42:56Z")

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Have looked in the log. Where I find these debug PID? Have found general Debug P, I,D but that shows nothing

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**Author:** ![kimbaku](https://avatars.discourse-cdn.com/v4/letter/k/8edcca/32.png) [@kimbaku](https://community.ecumaster.com/u/kimbaku)\
**Post date:** [November 11, 2024, 5:42am UTC](https://community.ecumaster.com/t/short-term-trim-correction/2731/6 "2024-11-11T05:42:25Z")

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Its in tab “others” and then “debug functions” and chose “shortTrim” and then make a log again and you Will see the controler at logs

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**Author:** ![Tagurit2365](https://avatars.discourse-cdn.com/v4/letter/t/b9bd4f/32.png) [@Tagurit2365](https://community.ecumaster.com/u/Tagurit2365)\
**Post date:** [November 12, 2024, 12:29am UTC](https://community.ecumaster.com/t/short-term-trim-correction/2731/7 "2024-11-12T00:29:17Z")

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What are some typical setting for short term trim? Standard they are somewhere around 3% and 5%, I think. I’ve gone all the way up to 40% (P) in order to get a decent response. What are others doing?

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**Author:** ![Tagurit2365](https://avatars.discourse-cdn.com/v4/letter/t/b9bd4f/32.png) [@Tagurit2365](https://community.ecumaster.com/u/Tagurit2365)\
**Post date:** [November 21, 2024, 12:35am UTC](https://community.ecumaster.com/t/short-term-trim-correction/2731/8 "2024-11-21T00:35:24Z")

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Any replies/thoughts about this? What is “typical”-ish?

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**Author:** ![Tagurit2365](https://avatars.discourse-cdn.com/v4/letter/t/b9bd4f/32.png) [@Tagurit2365](https://community.ecumaster.com/u/Tagurit2365)\
**Post date:** [December 2, 2024, 6:17pm UTC](https://community.ecumaster.com/t/short-term-trim-correction/2731/9 "2024-12-02T18:17:40Z")

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Bumping for any replies

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<div class="post-metadata">

**Author:** ![xsd](https://avatars.discourse-cdn.com/v4/letter/x/b5e925/32.png) [@xsd](https://community.ecumaster.com/u/xsd)\
**Post date:** [December 2, 2024, 6:30pm UTC](https://community.ecumaster.com/t/short-term-trim-correction/2731/10 "2024-12-02T18:30:19Z")

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I have P arround 60%

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<div class="post-metadata">

**Author:** ![Tagurit2365](https://avatars.discourse-cdn.com/v4/letter/t/b9bd4f/32.png) [@Tagurit2365](https://community.ecumaster.com/u/Tagurit2365)\
**Post date:** [December 2, 2024, 7:04pm UTC](https://community.ecumaster.com/t/short-term-trim-correction/2731/11 "2024-12-02T19:04:08Z")

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Thanks. That does help.

Until a couple of weeks ago I was trying to get these setup somewhere around the default range of 4 and 8 (or something small like that). Generally, PID doesn’t need a ton to be responsive, but at those low settings it was just slow as heck so I was confused by it. I recently spent an hour or so just driving and changing, driving and changing - watching data logs - and ended up in the P=45 and I=15 range, but it’s still not crazy accurate. It’s much more responsive, but has some behaviour that tells me it could be better. So, I’m just trying to get an idea what others have settled on.

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<div class="post-metadata">

**Author:** ![derUltraTT](https://avatars.discourse-cdn.com/v4/letter/d/ba8739/32.png) [@derUltraTT](https://community.ecumaster.com/u/derUltraTT)\
**Post date:** [December 2, 2024, 8:58pm UTC](https://community.ecumaster.com/t/short-term-trim-correction/2731/12 "2024-12-02T20:58:53Z")

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I think u already somewhere had a look on my settings. I used this in V2:

 ![image](https://europe1.discourse-cdn.com/flex013/uploads/ecumaster/original/2X/c/c27437eedd2f4921c3fee35c6c3443219a23f8ae.png)  
The PID has limits. The higher the better, but if too high u see osciallations. If u reached the highest possible gains without landing in osciallations u reached all u could in ur PID. If u then want more accuracy then u should look for other stuff depending on the behaviour.

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<div class="post-metadata">

**Author:** ![Tagurit2365](https://avatars.discourse-cdn.com/v4/letter/t/b9bd4f/32.png) [@Tagurit2365](https://community.ecumaster.com/u/Tagurit2365)\
**Post date:** [December 3, 2024, 2:47pm UTC](https://community.ecumaster.com/t/short-term-trim-correction/2731/13 "2024-12-03T14:47:35Z")

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Hahaha… I freely admit, I did look at your settings.

I am still curious what others are running for PID and the g/s correction tables.
