Lambda and Sensor overlay issue

FlashPro Manager software
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mladjan
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Joined: Fri Sep 23, 2016 7:16 am

Lambda and Sensor overlay issue

Post by mladjan » Thu Sep 05, 2019 6:09 am

Hi,

Im using latest Flashpro manager (v 3.4.3.0, build 1127).
On CIvic FN2 I have installed AEM X Series wideband controller (gauge) and connected it to ELD pin on ECU.
Based on table in AEM Documentation, I filled all settings which connect voltage to AFR value. Screenshot: http://cloud.mladjan.me/0de86a526955
Issue 1: AFR value on gauge itself is slightly different then value on Wideband input "sensor". Example: AEM Gauge shows 14.7, Wideband input shows 14.8. Its not huge thing, but would like to know what can be an issue?

Issue 2: (this is bigger issue)
Lambda/AFR value overlay on fuel cells is not using wideband input even I told him to use. It's using AFR Corrected.
This is how it looks: http://cloud.mladjan.me/cc8f2a2d7dc0
Lambda overlay settings: http://cloud.mladjan.me/62b30593ca74
Sensor overlay settings: http://cloud.mladjan.me/2560377604e3
I think that Bosh LSU 4.9 sensor is more precise then OEM corrected sensor, and I expect it to be used as overlay value when I set it in settings.

Datalog and calibration used on these screenshots: http://cloud.mladjan.me/2f1385abddbc

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Hondata
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Re: Lambda and Sensor overlay issue

Post by Hondata » Thu Sep 05, 2019 7:24 am

1. Most widebands use the same ground for the heater as the voltage output, so the heater current offsets the output. You can adjust in the calibration under 'Wideband voltage offset'. Keeping the wideband ground wire as short as possible helps too.

2. It works ok. I believe what you are seeing is the short term fuel trim adjusting the wideband value. You can switch it off under options to see.
Hondata

mladjan
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Joined: Fri Sep 23, 2016 7:16 am

Re: Lambda and Sensor overlay issue

Post by mladjan » Thu Sep 05, 2019 7:40 am

1. Ok, thx, Will try to adjust.
2. Where I can switch that off?
Btw, why will ECU use -5% Short fuel trim If I set target in WOT to be 12.8, and have that AFR on exhaust?

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Hondata
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Re: Lambda and Sensor overlay issue

Post by Hondata » Thu Sep 05, 2019 4:32 pm

2. In the settings for lambda overlay.

I think you're confusing the target lambda with the WOT lambda adjustment. Also, but going leaner than 12.5:1 in the WOT adjustment tables the ECU is now running closed loop the whole time.
Hondata

mladjan
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Re: Lambda and Sensor overlay issue

Post by mladjan » Fri Sep 06, 2019 5:54 am

Thx, I disabled fuel trims on lambda overlay, now it shows the same value as wideband: http://cloud.mladjan.me/5a890f3d2b7d
What is not clear to me is, if ECU will keep me in closed loop mode when I target 12.8 at WOT, wideband shows real value of 13.4, and Short fuel trim shows -5%. Negative value of should fuel trim means that I should add 5% of the fuel in fuel tables?

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Hondata
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Re: Lambda and Sensor overlay issue

Post by Hondata » Fri Sep 06, 2019 9:02 am

For whatever reason with the Honda ECU if your WOT compensation is leaner than 12.5:1 then the ECU will stay in closed loop.

If the fuel trim is -5% then you need to take out 5% fuel (or adjust the AFM calibration).

Now repeat after me ten times: the WOT compensation table is not a lambda target table.
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mladjan
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Re: Lambda and Sensor overlay issue

Post by mladjan » Fri Sep 06, 2019 11:55 am

Got it, thx :)

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