CUUA Engine - Negative soot mass measured

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pablo
Posts: 3
Joined: Tue Aug 04, 2020 1:28 pm

CUUA Engine - Negative soot mass measured

Post by pablo » Tue Aug 04, 2020 2:08 pm

Hi,

I'm successfully using app with CUUA Engine (Group 9) VW Jetta MK6 2016 year.
Yes I know (this engine is not officially supported).

The problem is that the soot mass measured value becomes negative after the firing process is completed.
Later this value increases from -11.88 to ca. 11.88.

I think that solution should be simple (adding correct offset to this parameter)
Is it possible to fix this in a newer version?

I can send logs if they are necessary for analysis.
Screenshot_20200320_105221_com.applagapp.vagdpf.jpg

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admin
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Re: CUUA Engine - Negative soot mass measured

Post by admin » Tue Aug 04, 2020 5:54 pm

It's no so simple: that value is somehow crazy, it doesn't increas linearly and becomes negative. I could add an offeset yes, but I don't do it because this strange value is exactly the same you can read in the official ODIS instrument of VAG. This is the reason why I never tried to correct the value, I think it could be useful in some conditions that I don't know yet. I received feedbacks about it reporting that in case of sensor failures, the soot mass measured field is the only one that gives reliable values. Never experimented personally.

If there is a use for this parameter (unknown for me), I can't modify its calculation formula.
If your engine runs without problems, you can ignore the measured value and read only the calculated one.

pablo
Posts: 3
Joined: Tue Aug 04, 2020 1:28 pm

Re: CUUA Engine - Negative soot mass measured

Post by pablo » Tue Aug 04, 2020 6:14 pm

Yes, engine works fine. Regeneration process also (starts every 250-500 km depending on traffic)

I just wanted to make sure the problem wasn't due to some oversight.
Thanks for the quick reply.

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admin
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Re: CUUA Engine - Negative soot mass measured

Post by admin » Wed Aug 05, 2020 8:39 am

Don't worry, this is a common problem for all engines. Soot mass measured meaning is still unclear.

Taking the opportunity of your post, I could add you engine to the app but I need some confirmations:
  • does "Regen duration" field increase during the regeneration?
  • does "Distance since last regen" field increase correctly compared to the real mileage?
  • does "Low press EGR closing" vaue is near 100 when the car is running at constant speed?
  • do "Post injection 2" and "Post injection 3" have values different from 0 during the regeneration?

pablo
Posts: 3
Joined: Tue Aug 04, 2020 1:28 pm

Re: CUUA Engine - Negative soot mass measured

Post by pablo » Sun Aug 09, 2020 11:05 pm

Hi,
I just got back from a weekend trip where I was able to take screenshots during the burning process.

All the parameters you mention look correct.

1. EGR valve closes aprox. 75%
2. Distance Since Since Last Regeneration is linearly dependent on trip counter

Look at screenshots listed bellow.
Screenshot_20200809_134428_com.applagapp.vagdpf.jpg
Screenshot_20200809_134657_com.applagapp.vagdpf.jpg
Screenshot_20200809_134849_com.applagapp.vagdpf.jpg
Screenshot_20200809_135044_com.applagapp.vagdpf.jpg
Screenshot_20200809_135300_com.applagapp.vagdpf.jpg
Screenshot_20200809_135527_com.applagapp.vagdpf.jpg
Screenshot_20200809_135629_com.applagapp.vagdpf.jpg

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admin
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Posts: 473
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Re: CUUA Engine - Negative soot mass measured

Post by admin » Mon Aug 10, 2020 9:55 am

Perfect! I'll add your engine type officially in the next update.

Thanks for the support.

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