# Warmup λ target correction table and short term trim

**URL:** <https://community.ecumaster.com/t/warmup-target-correction-table-and-short-term-trim/1461>\
**Category:** V3 SOFTWARE\
**Created:** [May 22, 2024, 5:52pm UTC](https://community.ecumaster.com/t/warmup-target-correction-table-and-short-term-trim/1461 "2024-05-22T17:52:11Z")\
**Posts on this page:** 7\
**Page:** 1

<div class="post-metadata">

**Author:** ![ChristianGrebe](https://dub1.discourse-cdn.com/flex013/user_avatar/community.ecumaster.com/christiangrebe/32/891_2.png) [@ChristianGrebe](https://community.ecumaster.com/u/ChristianGrebe)\
**Post date:** [May 22, 2024, 5:52pm UTC](https://community.ecumaster.com/t/warmup-target-correction-table-and-short-term-trim/1461/1 "2024-05-22T17:52:12Z")

</div>

Hi, I am a bit confused by the _Warmup - λ target corr._ table. Is this actually correcting the target λ for short term trim or is it just another means of trimming fuel calculation during warmup?  
If this is actually for correcting short term trim λ, is short term trim now working during warmup?

Thanks, Christian

---

<div class="post-metadata">

**Author:** ![Jadzwin\_ECUMASTER](https://dub1.discourse-cdn.com/flex013/user_avatar/community.ecumaster.com/jadzwin_ecumaster/32/28_2.png) [@Jadzwin\_ECUMASTER](https://community.ecumaster.com/u/Jadzwin_ECUMASTER)\
**Post date:** [May 22, 2024, 8:00pm UTC](https://community.ecumaster.com/t/warmup-target-correction-table-and-short-term-trim/1461/2 "2024-05-22T20:00:32Z")

</div>

Lambda is a part of fuel calcualtions.  
So changing any lambda tatget value / correction you always change the fuel dose.

The positive side effect is that short term trim will try to adjsut fuel to desired lambda target.

For example: if you correct fuel dose for high egt by for example 10%, and have short term enabled it will remove this fuel to be on lambda target.

If you scale the lambda target by 10% you get the same fuel dose increase (as a lambda target is a part of fuel dose calcualations), and the short term will not cancel this correction.

In V3 most correction are done for lambda target not injectors pulse width.

---

<div class="post-metadata">

**Author:** ![F\_MKIV](https://dub1.discourse-cdn.com/flex013/user_avatar/community.ecumaster.com/f_mkiv/32/510_2.png) [@F\_MKIV](https://community.ecumaster.com/u/F_MKIV)\
**Post date:** [May 22, 2024, 9:22pm UTC](https://community.ecumaster.com/t/warmup-target-correction-table-and-short-term-trim/1461/3 "2024-05-22T21:22:45Z")

</div>

![lambda target modify](https://europe1.discourse-cdn.com/flex013/uploads/ecumaster/original/1X/6dc4362b6b653bd7980ff09997eabc7418487415.jpeg)  
Is there a lambda correction table for IAT ?

---

<div class="post-metadata">

**Author:** ![ChristianGrebe](https://dub1.discourse-cdn.com/flex013/user_avatar/community.ecumaster.com/christiangrebe/32/891_2.png) [@ChristianGrebe](https://community.ecumaster.com/u/ChristianGrebe)\
**Post date:** [May 22, 2024, 9:27pm UTC](https://community.ecumaster.com/t/warmup-target-correction-table-and-short-term-trim/1461/4 "2024-05-22T21:27:32Z")

</div>

Great! Love that feature!

---

<div class="post-metadata">

**Author:** ![Jadzwin\_ECUMASTER](https://dub1.discourse-cdn.com/flex013/user_avatar/community.ecumaster.com/jadzwin_ecumaster/32/28_2.png) [@Jadzwin\_ECUMASTER](https://community.ecumaster.com/u/Jadzwin_ECUMASTER)\
**Post date:** [May 22, 2024, 9:36pm UTC](https://community.ecumaster.com/t/warmup-target-correction-table-and-short-term-trim/1461/5 "2024-05-22T21:36:15Z")

</div>

Fueling / Correction / IAT correction

But remeber the fuel calculations uses the IAT for calculating fuel dose.  
The IAT correction table is only for special purpose like for example adding extra fuel when IAT is high to prevent knocking. And then it is better to alter lambda than PW as it will work correctly with short term trim

---

<div class="post-metadata">

**Author:** ![F\_MKIV](https://dub1.discourse-cdn.com/flex013/user_avatar/community.ecumaster.com/f_mkiv/32/510_2.png) [@F\_MKIV](https://community.ecumaster.com/u/F_MKIV)\
**Post date:** [May 23, 2024, 10:23pm UTC](https://community.ecumaster.com/t/warmup-target-correction-table-and-short-term-trim/1461/6 "2024-05-23T22:23:55Z")

</div>

The recurring problem in traffic jams, IAT sensor is under heat soak, air density is less due to the falsely high IAT reading.

 ![IAT_short term trim](https://europe1.discourse-cdn.com/flex013/uploads/ecumaster/original/1X/c0f4c6d6eea5dc7d33fafdc8cf06e9131cb8534c.jpeg)  
We can only count on the “short term trim”.

---

<div class="post-metadata">

**Author:** ![Greg](https://avatars.discourse-cdn.com/v4/letter/g/71c47a/32.png) [@Greg](https://community.ecumaster.com/u/Greg)\
**Post date:** [May 24, 2024, 7:45am UTC](https://community.ecumaster.com/t/warmup-target-correction-table-and-short-term-trim/1461/7 "2024-05-24T07:45:55Z")

</div>

charge temp correction so when is on very low load temp is blended iat clt.  
if injector data is accurate you should be able to make it work nicely