DPF: Who has one and logs data?

Hi.

After being able to diagnose my 1Z through "listening," my BMR (basal metabolic rate) continues to be a source of mystery.

Yesterday, during a DPF cleaning cycle (with a laptop connected to the diagnostic port), the loading factor value 068.1 steadily decreased, despite the regeneration having just been completed and normal operation resuming afterward?

Does that mean that when the post-injection phase ends, the regeneration process isn't even complete yet?

Because, in reality, after the registration, the "gathering of resources" starts again, so it should mean more loading/carrying capacity, right?

Or is the coefficient just a computational model, and are the underlying "regulators" only just starting to "fade away"?

m;

Does that mean that when the post-injection ends, the regeneration process isn't even finished yet?

Hello Martin,

I've always understood regeneration in a way that the post-injection is only needed as long as the DPF is at a temperature where the particles can combust on their own. Once these particles combust, they continue to burn until either there is no more oxygen available (resulting in an interrupted regeneration) or there are no more particles left.
So, similar to a fireplace at home .

If post-injection treatments were required throughout the entire regeneration period, the IMA consumption would increase significantly.
Well, it's been going on for a few minutes now...

Best regards, Jochen.

He also injects it for a few minutes. (The longest injection time I saw in the logs was 3660 seconds).

The counters for failed injections, the injection timing counter, the post-injection amount, and even the DPF light (when it appears) all behave "simultaneously."
That means they start representing the same regulation simultaneously and are all finished at the same time.

After that, the exhaust temperatures also immediately decrease (I haven't yet observed temperatures after the DPF reaching 075.4).

Generally, when observing the DPF, the restriction to 3 MBytes in VAGCOM is very annoying, because you actually need 068..075 all at once. And they often also come in a bit slower than 20 samples per second .

The behavior of the DPF light indicates that the regeneration process is complete when it turns off. If you're already sending the customer on a wild goose chase, you might as well keep them there for a "long" time from a technical standpoint. The instructions don't say that you can immediately go home after the DPF light turns off. Therefore, it's finished after the post-injection process is complete.


Furthermore, I am still looking for a suitable set of monitoring worksheets (MWBs) to document the regeneration process.
Yesterday, I logged data with the IDs 067-068-070, but it's missing the temperature reading *after* the DPF (Diesel Particulate Filter) and some engine data that would indicate the driving style (e.g., RPM, fuel quantity).

m;

dieselmartin wrote:

Does that mean that when the post-injection phase ends, the regeneration process isn't even complete yet? Or is the coefficient just a computational model, and are the underlying "regulators" only just starting to "fade away"?

Hi Martin,

"My old DPF Gen1 system exhibits similar behavior. Once the temperature required for regeneration is reached, the load increases sharply, which is obviously due to the higher temperature inside the filter, where 1000°C is quite possible (the older models don't have a sensor after the monolith). The high temperature inside the filter persists for a while due to the mass of the monolith, so the actual value, which is derived from the intake temperature and the differential pressure, is somewhat higher – a higher temperature in the filter means a higher differential pressure. The question is, what does the MSGR (Engine Control Unit) use to determine the loading state? Differential pressure is clear, and the temperature at the filter inlet is also used, but how does the sensor after the filter come into play? Perhaps it's only used for diagnostic purposes to ensure a successful regeneration and to limit the maximum allowable temperature of the monolith (less than 1470°C)."

Hi Aron,

I didn't say anything about liability, maybe you just made a typo.

But even regarding the load, your answer doesn't fit, because in my case, the loading coefficient doesn't increase; it only continues to decrease, even when the registration should already be complete.

m;

Okay, by "load," I also meant what the French testers refer to as "belastet" (*g*). As I mentioned, it might be due to the temperature still present in the filter. This results in a higher differential pressure, and perhaps we can draw reasonable conclusions by examining the temperature sensor after the filter.

Based on my experience with my old wood-burning stove system, the burning process completes very quickly once the ignition temperature is reached and the chain reaction begins, and it is not interrupted by running the stove at full power and then turning off the motor.

Hi everyone,

I'm currently learning about my BMM (presumably referring to a specific piece of equipment or process), and I also logged a free-burning process.
My BMM (Base Load Management) behaves very similarly to Dieselmartin's BMR (Base Load Management). For about 5 minutes, the post-injection occurs, during which the temperature in the particulate filter rises to approximately 700°C, and the loading level decreases from 45% to about 10%. After another 10 minutes, a 0% loading level is reached. According to the control unit, the last 4.5% of loading was lost at a filter temperature below 400°C, which is quite strange and seems more like a theoretical value to me. During the post-injection, the soot index (MWB29 F3) increases to 384. I think this is why the remaining mileage display for the service decreases during the regeneration process, although I felt that the service display took longer than 5 minutes to reach the "low" level.

It's noticeable that in my MWB70, fields 2 and 3, which indicate successful and unsuccessful regenerations, are showing zero values. Given that the vehicle has 61,000 km (approximately 38,000 miles), this seems unlikely. Do you have any ideas about this?

Greetings.

They probably don't matter at all; I just glanced through about 10 scans.
and in none of them is there anything other than 0 displayed in the 70s section.
It was probably something that was considered but never actually implemented.

Maybe the unsuccessful attempts count when you finally succeed.
where the regeneration process would repeatedly fail due to a component defect.
But it's just an unproven theory.

Funny, in my BGW (additive system), the post-injection continues for 2 to 10 minutes even after reaching 0% load.

However, this only applies when "emergency regeneration" has been initiated.

I have never seen a gasoline particulate filter (GPF) on any of my cars (after 190,000 km), and I doubt whether it is even present. The normal regeneration or post-injection process sometimes only takes seconds; I can hear it from the turbo and see it in the instantaneous fuel consumption. It's as if it briefly ignites the soot and then continues. Sometimes, however, it takes minutes.

Currently, I'm worried about potential issues during regeneration due to a hole in the flexible pipe after the turbocharger. It wouldn't be very pleasant if 760 degrees Celsius of hot exhaust gas were leaking out.

At 760 degrees, the BGW actually limits the temperature before Turbo mode is engaged; it's not possible to go any higher.

vagtuning wrote:

They probably don't count at all; I just glanced through about 10 scans. and in none of them is there anything other than 0 displayed in the 70s section. It was probably once considered, but probably never implemented.

Okay, well, at least I don't have to worry about that anymore, although I was actually quite interested in it.

Benni wrote:

By 760 degrees, the BGW actually limits the temperature before Turbo; it can't go any higher.

"In one particular instance, my boost pressure sensor (BMM) registered 834°C, which is quite high for a diesel turbo. Now, I'm thinking about the fact that I once stopped my car right in the middle of a regeneration cycle, ouch..."

EDIT (two weeks later):

I have logged further generations and was able to observe the following:
If a 45% load is not reached, the regeneration cycles seem to occur at fixed 400km intervals. Even with a lower load, the regeneration process starts after approximately 385km, so that after 400km, the counter 73.01 (distance since regeneration) is reset.

70.01 Regeneration time.
Normally, it starts at 0, and the regeneration duration increases in steps of 50 seconds. After a post-injection (199.7 seconds), I had to briefly reduce the throttle, and the post-injection stopped momentarily. It then displayed 70.01, and remained at 0, despite the regeneration continuing.

69.00 (Status 1 - Regeneration)
"At the moments when the post-injection is interrupted, the value is 10,000,000 (otherwise it's always 0), unless the engine is idling."

At the lowest engine speeds with post-injection, I was able to record 1155 RPM.

Post-injection occurred over a period of 15 minutes, with a total injection time of approximately 10 minutes. Notably, post-injection continued for 3.5 minutes even after a 0% loading coefficient (68.0) was reached, in order to maintain the filter temperature above approximately 650°C. In contrast, during my previous regeneration test run, the situation was the opposite.

Another run with almost no (a brief) interruption of the injection lasted 10 minutes, even though 0% was reached after 7 minutes.
Starting at 520°C in the PF zone, the loading factor began to decrease.
In one instance, I was still able to drive for 40 minutes with a 0% charge level, even though the battery cell temperatures were below 400°C. I simply can't figure out the charging coefficient.

Maximum temperatures:
Particulate filter, 702°C.
Turbo 834°C

"The stubborn forced regeneration can sometimes be really inconvenient. The other day, I drove several kilometers on the highway, normally, at a brisk pace, with the accelerator fully pressed. Then, when I was stuck in a longer traffic jam, a forced regeneration process started. Unfortunately, I didn't have my laptop with me, but since the remaining kilometers until the next service check disappeared unusually quickly, the regeneration process must have lasted for an unhealthy amount of time. If the engine control unit had a small buffer for forced regeneration (perhaps it was already set that way, I don't know if the vehicle was loaded to 45%), it could have started the regeneration, for example, "3 minutes after reaching 50 km/h or 1600 RPM" or "3 minutes after the last stop-and-go cycle"... "

Greetings.

Hello everyone,
mein nachgerüsteter O***land Partikelfilter (replace Oxi-Kat) verbrennt den Ruß laut Hersteller ab >250°C. Gibt es irgendwo Infos ab wann 250°C kurz hinter Turbo (abfallendes Rohr zwischen Turbo und Abgasanlage Unterboden) erreicht werden? SicCan you help her very quickly?!
Are there still temperature diagrams available that depend on engine speed/load/speed, for example, for a 74 kW TDI engine (something like a shell diagram)?
You're welcome, haithamina.
"Measurements on various vehicles have shown that, depending on the application, the particulate filter catalyst can reduce particulate matter (PM) by between 30 and 45%. The particulate filter catalyst is particularly effective when exhaust gas temperatures exceed 250°C for sufficient periods of time."

haithamina wrote:

mein nachgerüsteter O***land Partikelfilter (replace Oxi-Kat) verbrennt den Ruß laut Hersteller ab >250°C. Gibt es irgendwo Infos ab wann 250°C kurz hinter Turbo (abfallendes Rohr zwischen Turbo und Abgasanlage Unterboden) erreicht werden? SicCan you help her very quickly?! Are there still temperature diagrams available that depend on engine speed/load/speed, for example, for a 74 kW TDI engine (something like a shell diagram)? You're welcome, haithamina. "Measurements on various vehicles have shown that, depending on the application, the particulate filter catalyst can achieve reductions in particulate matter (PM) between 30 and 45%. The particulate filter catalyst is particularly effective when exhaust gas temperatures exceed 250°C for

sufficient periods of time}."

Hi,

I can't provide any log files, but I can offer readings from my display. The vehicle is a CR Gen1 (Euro3) with 6-hole injectors and factory-installed exhaust restrictors, manufactured in 2002, and has a "faulty" EGR valve.

"At 90 km/h with GRA (presumably referring to a specific driving mode or condition), I measured temperatures of 250-275°C directly after the ATL (presumably referring to a specific point or event) on a straight road at -10°C. On inclines with an estimated 5% gradient, the engine then runs in 5th gear at 90 km/h with 1800 rpm, producing approximately 400°C. With a functioning EGR (Exhaust Gas Recirculation) system, the temperature at partial load was 25-50°C higher, but only above 70°C coolant temperature; below that, the MSGR (presumably referring to a specific control system) allows the EGR to operate."

You should also consider the mass of the filter; it can only regenerate when the filter itself is heated. Therefore, the temperature after the filter is crucial for regeneration. Directly connected to the turbocharger, I have an approximately 15 cm long catalytic converter, and below the downpipe and before the filter, there's another catalytic converter of the same size. The connecting pipe between them is approximately 40 cm long. The temperature delay after the air intake manifold is minimal, about 10 seconds under moderate load. However, the delay after the catalytic converters or before the filter is about 30-60 seconds, which is likely due to the mass of the components, and probably corresponds to the mass of your filter.

If the filter truly burns off soot at 250°C (which I'm not entirely convinced of, as those are likely just the manufacturer's desired values), then it should start regenerating during extended city driving in the summer.

Hi Aaron,
Thank you for the information about the likely temperatures at Kat. I would have expected higher temperatures when traveling at 90 km/h and using GRA, especially when going towards ATL. Do you have any information about the temperatures after ATL at a constant speed of 130 or 140 km/h with GRA? I usually drive in that speed range (3000 RPM).

haithamina

P.S.

Aron wrote:

With a functioning EGR system, the temperature at partial load was 25-50°C higher, but only above a coolant temperature of 70°C; below that, the engine control unit (ECU) allows the EGR to operate.

The above statement regarding the EGR system is also interesting (actually, it belongs to a different thread), as there is still ongoing discussion about whether an engine with a functioning EGR system warms up faster.

Quote:

Constantly 130 or 140 km/h with GRA? I usually drive in that range (3000 RPM).

Because you're considering getting a 3C.

At 3000 RPM, my actual speed was 160 km/h (the speedometer showed almost 170).
The increased air resistance will certainly also have an effect on the exhaust stream.

m;

dieselmartin wrote:

Because you're considering getting a 3C. m;

Well, currently I'm leaning towards a Schgodda Super B Combi, as it's (slightly) larger and has the same technology for less money.

haithamina

Hm.

"The Supperp doesn't actually come in a blue color..."


And in the trunk, I already see a drawback that contradicts the claim of being "slightly larger."
The compartments located behind the wheel arches are designed as folding compartments.

It's not the case with the Passat, and I've often used that exact space for particularly bulky items!

In addition, the 3C has a 10-liter larger fuel tank.
.. is allowed to smoke more.
... has a rear window that is not quite as flat.