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chris
Joined: 11/05/2019 Posts: 8 Karma: +0 / -0 Location: wien
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20-08-2021, 2:10 Subject: DPF soot mass measured as too high |
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Hello from Vienna.
The filter in my 2012 Q7 4L 3.0L was flushed by a company that specializes in DPF cleaning.
A regular train journey was conducted.
*The differential pressure sensor was recalibrated (and the lines were also cleaned).
*then adjusted to 30,000 km (on the safe side, since it's not new).
So the question is:
The measured black carbon mass is very high, as shown in the image.
I've had some before, but never experienced this kind of problem!
Address 01: Engine Control Module (J623-CJMA) Label file: . DRV\059-907-401-V2.clb
Part number SW: 4L1 910 401 J, Part number HW: 4L0 907 401 C.
Component: 3.0TDI EDC17 H37 0002
Revision: 53H37--- Serial number:
Encoding: 2A2A4012A52601020000
Operating number: WSC 31414 790 00001
ASAM Dataset: EV_ECM30TDI0114L1910401J 001002
ROD: EV_ECM30TDI0114L1910401J.rod
VCID: 2A62990C4D4BF81AAB-807E
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Translated on 03-07-2026, 15:19.
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matthiasTDI96 Profi-Schrauber

Joined: 02/27/2003 Posts: 5886 Karma: +251 / -0
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20-08-2021, 6:41 Subject: DPF soot mass measured as too high |
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Hi,
Okay, I don't really see anything seriously wrong here. The pressure is building up (both theoretically and practically, measured by the interpolated pressure drop, which is why there's an offset during the learning phase) until it regenerates. Since the regeneration, you seem to have driven approximately 400 km.
As soon as the next regeneration cycle begins, the coal will be burned to ash.
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Herbert Profi-Schrauber

Joined: 06/22/2005 Posts: 4586 Karma: +1319 / -0
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20-08-2021, 7:02 Subject: DPF soot mass measured as too high |
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Hi,
The measurement, which involved a 400 km driving distance since the last regeneration, was taken before the flush. I wouldn't have seen anything there either; even during the ash loading, there wasn't a reason to flush the DPF.  370 ml is the limit, isn't it?
The soot level in the second image seems a bit high, but it would be helpful to know if this is the first recording after a cleaning cycle, or if the system is now regenerating much more frequently. If so, the process continues with a recording of the differential pressure.
hg
Herbert.
Horch A4 8K CJCD
Golf 7 DDYA
(+ Audi 80 Avant B4 1Z 475Tkm - habe ich vom ersten bis zum letzten Tag gerne gefahren)
(+ Passat Variant 32B CY 400Tkm)
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chris
Joined: 11/05/2019 Posts: 8 Karma: +0 / -0 Location: wien
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20-08-2021, 8:24 Subject: DPF soot mass measured as too high |
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Hello.
Thank you for the quick response.
The 370l figure is correct, but I didn't want to close it completely.
I'm afraid that the flush may have damaged it.
Because how does he immediately get such a high measured soot value?
That's not normal.
Normally, the measured and calculated values are almost the same, right?
I still have a B7 ASB with 120,000 km that needs regeneration every 800-1200 km.
The Q7 has always had around 300-400 kilometers on it since its last oil change, and I wanted to give it a fresh oil change now.
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matthiasTDI96 Profi-Schrauber

Joined: 02/27/2003 Posts: 5886 Karma: +251 / -0
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20-08-2021, 8:45 Subject: DPF soot mass measured as too high |
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He simply calculates it based on the differential pressure parameter. There's an adjustment that depends on the load, and you've now specified that by entering approximately 30,000 km. I also experimented with the mileage values after the flush. I once achieved an optimum performance at 12,000 km.
How did I get here? I've repeatedly logged differential pressure readings during idle after regeneration, and I've also searched for data online. I then did some interpolation and arrived at a "very clean" differential pressure value after the flush. It seemed to fit well in my case. Do you have any data on that? If so, we can take a look.
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chris
Joined: 11/05/2019 Posts: 8 Karma: +0 / -0 Location: wien
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20-08-2021, 8:54 Subject: DPF soot mass measured as too high |
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Thank you, thank you.
I'll be able to get to it again next week.
I'll take a few more logs and then report back.
Best regards, Chris.
Translated on 03-07-2026, 15:19.
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dieselschrauber Administrator


Joined: 04/12/2002 Posts: 18003 Karma: +784 / -0 Location: St.Gallen 2018 Volkswagen T6 
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20-08-2021, 9:03 Subject: DPF soot mass measured as too high |
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Hello.
Quote: | | The Q7 has always had around 300-400 km since its last oil change, and I wanted to give it a flush this time. |
Never touch a running system.
I am still missing some basic information about the vehicle, such as the mileage, etc.
As long as the regeneration process occurs at reasonable intervals and is successful, and the pressure difference does not become too high, I see no need for action.
Sure, I'd be happy to translate the text for you. Please provide the text you would like me to translate from German to English.
Okay, I'm ready. Please provide the German text you want me to translate.
Best regards, Rainer.
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chris
Joined: 11/05/2019 Posts: 8 Karma: +0 / -0 Location: wien
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21-08-2021, 2:27 Subject: DPF soot mass measured as too high |
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hi
Never touch a running system.
You're right, but I've had some issues with loading before, and then encountered problems.
Just for your information, here are the data and another log entry from today.
Is the differential pressure reading okay?
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| DPF soot mass measured as too high |
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Log-WAUZZZ4L8CD036437-189330km-Q7 scan 29.5.2021.txt |
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dieselschrauber Administrator


Joined: 04/12/2002 Posts: 18003 Karma: +784 / -0 Location: St.Gallen 2018 Volkswagen T6 
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22-08-2021, 18:56 Subject: DPF soot mass measured as too high |
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Hello,
Yes, the differential pressure looks good.
Best regards, Rainer.
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chris
Joined: 11/05/2019 Posts: 8 Karma: +0 / -0 Location: wien
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22-08-2021, 22:58 Subject: DPF soot mass measured as too high |
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I agree.
But the measured soot mass is too high, isn't it?
I don't understand how he arrived at that value so quickly.
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Herbert Profi-Schrauber

Joined: 06/22/2005 Posts: 4586 Karma: +1319 / -0
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23-08-2021, 6:42 Subject: DPF soot mass measured as too high |
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Quote: | | The soot loading in the second image seems a bit noticeable, but we would need to know whether this is the first recording after the cleaning process, or whether regeneration is now happening much more frequently. |
Is it being regenerated more often now? What were the testing conditions, and what were the air mass and boost pressure values during the differential pressure measurement?
Herbert.
Horch A4 8K CJCD
Golf 7 DDYA
(+ Audi 80 Avant B4 1Z 475Tkm - habe ich vom ersten bis zum letzten Tag gerne gefahren)
(+ Passat Variant 32B CY 400Tkm)
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matthiasTDI96 Profi-Schrauber

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23-08-2021, 6:57 Subject: DPF soot mass measured as too high |
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There are also over 183,000 km since the last regeneration... perhaps there's some confusion. Drive until the next regeneration cycle, or initiate one manually and then observe the new cycle.
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vag-driver Profi-Schrauber

Joined: 01/03/2015 Posts: 938 Karma: +400 / -0
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23-08-2021, 14:13 Subject: DPF soot mass measured as too high |
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What exactly was done during the flushing process? I hope no additives were added. For me, there is only one reliable method to have this done: [url][/url]https://www.russfilterreinigung.de{MARKER}.
Viele Grüße
Andreas
*** Ein Ingenieur muss vordenken. Wenn er anfängt nachzudenken ist es schon zu spät. ***
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