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  #126  
Old 02-09-2019, 04:24 PM
RPsX5d RPsX5d is offline
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Quote:
Originally Posted by mitocross View Post
. . . The reason why you do have mileage differences in you table is, because there are intermediate regenerations happening (for various reasons and needs - triggered by the computer). Those often end earlier and do not reset the "counter" - meaning, no successfully finished regen is recorded, even though your soot will be low low.
160-200miles between (or approx 200-300+) is a normal distance between two regens happening (in reality), and likely happened even though it recorded 300+ miles in the table. I have been checking this very often.

And I have an Euro E70 and I cannot trigger a regen before calculated soot level reaches 50g, in any case.
You are absolutely right . . . I have noticed EGT climbing up to 300-350C and holding . . . I call these passive regens, and they do not reset the regen counter. Next time I observe these I will keep an eye on the soot level.

Yes, I assumed the soot in grams is a Carly computed value . . . for my purposes it is good enough, I am only looking to see what is happening, not looking for an exact measurement.

Quote:
Originally Posted by smassey321 View Post
. . . Is Carly the best tool for manually kicking off a regen while driving? I own carly it but rarely use it because I prefer ISTA+ and a laptop size screen.
For me Carly was the best option - OBD reader remains in the car (unplugged), so the setup to monitor takes less than half a minute . . . dragging a laptop out each time I want to monitor something is just too tedious.

Quote:
Originally Posted by mitocross View Post
You will not be able to trigger regens manually.Carly "waits" until 50g soot level is reached before triggering a regen even when you do a manual request.
But you also need parameters for regeneration - temperature, rpms, speed, no fault codes, ...etc. That is hardly achievable with cold morning starts and short distances.
Didn't know this . . . there is a manual regen function in Carly, never used it . . . for me, almost always, when soot level reaches ~30 grams, the car triggers an active regen, and about 15-20 minutes later, soot level is down to near zero and EGT drops first to ~300C and then back to normal running temp (about 230C). After a key-off, the regen counter resets by one.
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  #127  
Old 02-10-2019, 02:22 AM
mitocross mitocross is offline
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Quote:
Originally Posted by RPsX5d View Post
Didn't know this . . . there is a manual regen function in Carly, never used it . . . for me, almost always, when soot level reaches ~30 grams, the car triggers an active regen, and about 15-20 minutes later, soot level is down to near zero and EGT drops first to ~300C and then back to normal running temp (about 230C). After a key-off, the regen counter resets by one.
We probably have a little different versions of engines because of where we live. Try the manual request in Carly. For me it never did anything. Always waited for min. 50g of soot.
30g for my car is sort of a mid level.
After regen finishes in my car, the counter immediatelly sets value to 0 or 1 - depends if it was completed to 0g or not. Key-off has no effect on this.
Just some interesting differences.
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  #128  
Old 02-10-2019, 09:05 AM
RPsX5d RPsX5d is offline
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Quote:
Originally Posted by mitocross View Post
We probably have a little different versions of engines because of where we live. Try the manual request in Carly. For me it never did anything. Always waited for min. 50g of soot.
30g for my car is sort of a mid level.
After regen finishes in my car, the counter immediatelly sets value to 0 or 1 - depends if it was completed to 0g or not. Key-off has no effect on this.
Just some interesting differences.
Yes, I will try and do a manual regen next time the soot level is over 25 grams and see what happens.

My X5d:
X5 E70 LCI BMW X5 35dX // Type Code: ZW03 // Type: GEFZG // Engine: M57Y

Key-off . . . I was referring to the no. of successful regen read by Carly . . . e.g. if the counter was at 570 and an active regen is triggered, you will notice the soot level drop, after the soot level reaches close to zero, the EGT will start to drop . . . but the 570 number stays the same. The next time I start the car, the regen counter will read 571.

Soot level and when regen is triggered varies a LOT . . . I have never seen a regen triggered with soot level below 15 grams . . . all of the regens I have observed were above 20 grams . . . some as high as mid 30 grams . . . I don't recall seeing a soot level over 40 grams.

As others have pointed out - many parameters have to cross a threshold before an active regen is triggered, the soot level is only one of the many. I only watch the soot level to see if the active regen takes the soot level down to near zero grams. Again the soot level figure is a Carly computed number, so, at best, a decent estimate.
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  #129  
Old 05-07-2019, 06:18 PM
rodentmaster rodentmaster is offline
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Mein Auto: '08, 3.0D X3. ~100,000km'
2008 E83 X3 3.0d.......overall, has not been a great experience with this car but if nothing else, I have become used to or 'adapted to' to what's required to keep the engine performance somewhat consistent.
DPF....like others here have outlined, continues to be central to the demise of the power output but, as I have learnt from the car I have, it reads as if there are multiple attributes with these engines that "have to be" at 100% for engine to be optimal......any hint of a part or item being out of spec tends to result in the fuel management going way off song.
Type of oil is critical. I replace oil & filter every 10,000km.....regardless of the so called extended service life fodder.
I have a pattern where I drop out the DPF every 3 months and clean it by a loose method of soaking it with up to 2 cans of oven cleaner and a bottle of methylated spirits.....vigorously hose it out between doses of oven cleaner.
Not a pretty process.

After a clean, reset the adaptive settings and perform a DPF pressure test via DIS.......essential.

Items which have defeated or affected the DPF operation on the car ......
Glow plugs
Oxygen sensor
DPF temperature probe
EGR valve clogged

Glow plugs are constantly failing.....every 12 months a new batch start to fail....... a real PIA to change as the manifold has to be off to complete the swap - had one controller fail as well.
Oxygen sensor - original unit was not faulty but as I had discovered via other forums, oxygen sensors don't fail outright per say but rather they become less sensitive or response times become lethargic. Replacing the oxy sensor "seemed" to increase the length of period between DPF cleans and DPF appeared to be not so dense of soot when cleaned out (possibly less fuel burnt??)......purely my subjective observation.
DPF temperature probe damage by previous owner.
EGR valve (at throttle body) constantly clogged and cleaned every 3 months with the DPF.

In essence what I have learnt, the use of diesel power in a family based car is not suitable operation to live day to day low load/low speed driving.
Diesel engines are best at full load.... I cannot manage that.
Diesel is a bi-product fuel - a dirty fuel.
Any systems engineered to "clean" the exhaust, then potentially become the problem and so on and so on.
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  #130  
Old 05-09-2019, 08:55 PM
ChrisM011 ChrisM011 is offline
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This may have been said in the previous 130-or-so posted, but Ive gone through a bit of a learning curve. Here is the summary:

1) use engine oil specific to modern diesels. Edycol knows a lot. Check his posts. Change oil more frequently than BMW spec. My preference is every 5,000 miles, but this can be debated forever.

2) almost all downstream DPF issues are caused by upstream problems. Check all vacuum hoses and any hose that carries pressurized air. In my opinion, charge air cooler hose seals need to be replaced at a particular mileage/time interval. Also, the MAP sensor (near the back of the intake manifold) should be replaced preventatively at something around 100,000 miles. Also, the small hose that works as our PCV generally starts to leak/crack after a number of years/miles. Replace it. AARodriguez makes a replacement for $15...with a lifetime warranty.

3) Highway drives are important. The DPF and SCR need to get up to temperature to work properly. This also means check your thermostat. The exhaust also has temperature and pressure sensors that I am sure have a useful life.


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  #131  
Old 07-04-2019, 03:29 PM
AU Pete AU Pete is offline
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just to provide a further data point to all things DPFs and swirl flaps...

I had the swirl flaps removed and capped about 2 years ago in mine. The caps used were supposedly good quality (purchased from the UK for about $90AUD) but a few failed after 2 years and I developed an oil leak. Had the mechanic investigate and he thought the o rings used were not up to the task. He replaced the caps with a new improved model that his shop had had developed by a local engineering company that makes bespoke parts. Fitted now and so far so good.

Interestingly - the mechanics own car was a LCI e70 x5 - and he was just as frustrated with the DPF in his own car. He, like Mitocross, had come to the conclusion that the swirl flaps are necessary particularly when coupled with lots of idling/driving in the city. He was investigating having some reinforced bespoke swirl flaps made up to couple with a reconditioned manifold - along the lines of what Mitocross did with a reconditioned unit from https://www.pmgtechnik.com/en

So I'm interested to see what happens with his car - then may or may not do the same with mine. if the new swirl flap caps don't leak and it doesn't throw any DPF errors for a while maybe i can limp to the end of ownership with it - i give it a few more years

Pete
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  #132  
Old 09-03-2019, 12:56 AM
mitocross mitocross is offline
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Here is an update about the PMG Technik manifold with new reinforced swirl flaps I installed 6 months ago:
All six flaps developed leaks around the axles and fittings. Five months and 15000km ran. Whistling of air escaping around the flaps was heard later. I had to have the manifold removed and installed a new OEM manifold with original swirl flaps. The "old" manifold has just been picked up by UPS to be inspected by PMG. I will update after I have news from them.
So the PMG option seems not so good now. I was very optimistic about it at first.

Last edited by mitocross; 09-03-2019 at 12:57 AM.
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  #133  
Old 10-09-2019, 05:15 PM
AU Pete AU Pete is offline
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update on the car from the original post - wow - almost 3 years ago since this thread was started...

car is going fine but generally reverting to he DPF regenerating too frequently for my liking (about every 150km for city driving).

my mechanic reported he had a good result with his own car when he removed the blanking caps and reinstated swirl flaps - much like the experience from mitocross earlier in the thread. obtaining *new* swirl flaps is a difficult path though it seems as a new genuine manifold costs several thousand AUD i think (and the swirl flaps are not sold as an individual part). My mechanic is able to source a chinese-made replacement manifold from the US apparently for about $700AUD landed (so about $1000 AUD fitted), and has suggested using just the swirl flaps in it in combination with the original manifold. That is what he did with his own car and noticed a difference in that the soot measured was not rising as rapidly during city driving (low revs - lots of stop start)

so this is really just an update - I'm not sure i want to do that - or just leave it. the car is getting on in age now, and i'm generally nervous about the longevity of some non-genuine swirl flaps from a different source potentially failing. If any of the more senior members want to chime in with their thoughts itd be appreciated.

I suspect if i keep going we might be back at the original starting point of DPF full error on the idrive screen within a year
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  #134  
Old 10-10-2019, 09:45 PM
ChrisM011 ChrisM011 is offline
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I recommend not going the inexpensive Chinese route on something like this. Cheap plastic is much more likely to break apart under load - and in this case that means plastic pieces moving toward the cylinders of the engine with potentially catastrophic results.


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  #135  
Old 10-11-2019, 04:20 PM
AU Pete AU Pete is offline
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I recommend not going the inexpensive Chinese route on something like this. Cheap plastic is much more likely to break apart under load - and in this case that means plastic pieces moving toward the cylinders of the engine with potentially catastrophic results.
thanks - yeah i'm leaning that way i think.
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  #136  
Old 10-11-2019, 04:36 PM
keliuss keliuss is offline
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Hi Pete,

I replied here over 24 hrs ago detailing some very interesting findings I've made over the past year collecting data and the post seems to be in forum limbo awaiting moderator approval. Not sure why, possibly because I had a few screenshots in it.

If I don't hear anything soon I will try again.

Keliuss

Edit: well this got posted. There might be a limit as I'm such a newbie here.

Last edited by keliuss; 10-11-2019 at 04:38 PM.
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  #137  
Old 10-11-2019, 04:43 PM
keliuss keliuss is offline
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Hi Pete,

I'm not an active member here, but am pretty active on forum.bmw5.co.uk where I've made some related posts. Sorry this is a long read but quite a few details to cover.

Like you, I've been monitoring readings for over a year now and made some great discoveries/observations. I originally had exactly your symptoms and observed exactly what you did in terms of regens and soot mass. My car was blindly doing regens, sometimes one after another without me knowing until I looked.
I suspect there are many more owners ignorant of this issue.

There are a few other considerations you need to factor in to get a clear picture of what affects regens. I will go into detail on each.

1: Potential design flaw/oversight in the backpressure sensor design.
2: The slight discrepancy/bias of the backpressure sensor reading.
3: The weather, specifically atmospheric pressure (AP) and the flaw in how the car uses it.
4: Altitude, again atmospheric pressure (AP)

Something else of note is that swirl flaps are always open below 15C intake air temp. More on that later.

My engine is N47 with about 190k kms on the DPF when I first looked into this issue. It is now at 222k, so it's pretty old DPF-wise.
I have largely addressed the causes and it's regen interval is now in the 300 to 500km range which is probably about right given it's age.

1: Design flaw
On a few occasions while driving I noticed my backpressure differential reading (BP) was high (up to 100mb differential above atmospheric pressure) even when parked/engine at idle. A regen would soon follow and I thought my filter was really clogged, as pressures would not reduce much or by anything sometimes. A regen would complete, only for the (virtual) soot mass to rise again to about 42g within 10-20km, for another regen to start. Overall the BP readings were very inconsistent and I was struggling to find a pattern.
One day I noticed the BP reading stayed at 80mb above AP after I turned the engine off and did not drop even after a few minutes. For this reading to be true the exhaust would have to be bunged/clogged/sealed hermetically. Knowing this was not the case, I suspected my OEM sensor was goosed, so ordered a replacement, which was a cheaper brand (FAE). After fitting the new one I noticed it doing the exact same thing a few days later. Two sensors, same results.

I confirmed my Torque app readings were correct with ISTA-D and here is a pic of my pressure readings with the engine off.

A discrepancy of 83mb between exhaust reading and ambient, when they should both be the same. This will result in almost constant regens as the car interprets this as heavily clogged filter and the soot mass rising very quickly. Note that the ambient reading here comes from the DDE unit.

So some further research into how the sensors work ensued. Some older types used two pipes on both sides of the filter to arrive at a differential reading. The newer types (like mine) use just one pipe pre-filter. But they need another source to get a differential reading. I found the answer on the FAE website. The sensor body has a hole somewhere to get atmospheric/ambient pressure. The only hole I could find on mine was beside the pins inside the plug opening.

But this hole is situated behind the tight rubber waterproof seal of the plug, so how can it read an accurate ambient pressure behind there? Well it can't. Therein lies problem number 1.


continued in next post..............
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  #138  
Old 10-11-2019, 04:46 PM
keliuss keliuss is offline
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..............continued

Admittedly I was very sceptical that this was causing a problem but I wanted to eliminate it from enquiries so I drilled a 1mm hole into the plug opening on the far side of the rubber seal to ensure the original hole is open to ambient pressure.

I did not drill into the sensor body, and yes, it's no longer sealed/waterproof but so what! In hindsight I should have drilled on the underside instead of the top. Fellow member both here and on bmw5, GoNz0, suggested I could have just pulled the rubber off the plug, probably easier

This potential design flaw seems hard to believe but I have never seen the large discrepancy in readings ever since doing this about 7 or 8 months ago. When I turn off my engine now the BP always drops instantly, and my regens started to become less frequent. This leads me on to number 2 on my list:

2: Sensor reading bias
With the above issue resolved I got the following results with engine off:

Note the discrepancy of about 20-25mb. Both my charge pressure and exhaust BP are higher than ambient. They should all be the same with engine off, even though BMW say +/- 50mb is ok. Just 20-25mb bias causes the very sensitive soot mass calculations to rise far too easily. I've seen other peoples readings and they always seem to have this positive bias of about 20mb on both of these sensor readings.
I've read that this "offset" can be manipulated with Tool32 but I've not found a good guide on how to change it so went a different route.

The BP sensor is resistance based and receives 5 volts power and returns a varying voltage (1-4volts or something, can't remember exactly) dependent on the pressure. An increase in resistance equates to a lower pressure reading. So I cut the voltage return line and started adding in resistors until the BP reading was aligned with ambient. Ended up soldering in about 3k Ohms (again, can't remember exactly). The result:

It now reads within +/-5 of ambient. Don't forget this is an engine off reading.
This has helped regen intervals even further and this is where the car is at currently with regens now in the 300-500km range.

But by far the biggest factor is...

3: The Weather and 4: Altitude
Hard to believe, I know. For this you need to know your Meteorology, specifically Atmospheric Science.
I'm putting these two aspects together as they are two sides of the same coin.
I live in Dublin, Ireland at sea level (more or less). On average the ambient pressure is 1013mb at sea-level the world over. It obviously varies day to day and when on my commute to work I can actually tell if it's a high pressure day (say 1033mb) or low pressure day (993) based on how fast my soot mass readings are going up.

For simplicity lets just look at those 2 examples. On a high pressure day (1033mb) my BP readings will be low and soot mass only rises at about 0.1g per couple of kms. On days when I see the soot mass rise quickly I know it's a low pressure day even before I check, and this often leads to a regen on my 46km commute to work.

Obviously the weather varies and most days are somewhere inside this range, leading to variable length regen frequency that have little or nothing to do with actual soot mass.

Now the altitude aspect. Ambient pressure drops as altitude rises. To the south of Dublin are the Dublin/Wicklow mountains. If I drive from my home (at sea level) up into the mountains (hills really) to an altitude of only 300m my BP readings go up up up. Turn the car around, go back down and the BP readings go back down.
At 300m altitude ambient pressure drops to 977mbar. The car BP on average stays relatively constant. It is only the ambient pressure that has changed, but the car interprets this as increased BP and starts clocking up the soot mass readings. Seems ridiculous right? But this is the reality.

In a related thread some months back over on bmw5, GoNz0 suggested maybe the car takes a baseline AP reading when the engine starts and uses this. I said no, that would be ridiculous - if you drive up a hill (like in my example above) the AP drops so the car would be using bad/incorrect readings in the calculations. But I have now concluded that he was dead right. It does this exact ridiculous thing.

I drove to Madrid last June in stages over a few days. I started one day on the French coast (sea-level) and Madrid at 667m above sea level was the destination. I knew what was going to happen. The BP readings went through the roof while on the road, maybe 100mb differential at idle but I saw peaks of 300mb under load and I could do nothing to stop the constant regens that followed. What I wasn't so sure about was if all BMW's in the center of Spain suffer from constant regens. Surely not. After a long lunch that day the car had gone to sleep mode and I was expecting the BP readings to normalise or something. They didn't. I continued on to Madrid with more regens along the way. It was only the next day in Madrid after starting the car that the BP readings were back to normal. So it took a few sleep cycles before the car accepted the lower ambient readings. Regens were back to normal frequency then. On the return journey back to sea level it was all in reverse, my BP readings went negative. About -100mb or so. How ridiculous is that? On this leg of the journey I saw a regen interval of 1000km (exactly).

So there is a major flaw in how the car takes and uses an ambient pressure reading. To me, this flaw could be removed if the car took a baseline reading say every few minutes, instead of every few car sleep/wake cycles. Maybe BMW engineers are "flat" Earthers lol and don't bother to consider it has terrain.

Now for some of what I haven't yet figured out. In Madrid, after the second day and with the car/regens back to normal, the car would read the correct AP as around 935mb, which was bang on for the altitude. But with the engine running at idle the exhaust BP readings would be in the same region I'm used to no matter the altitude, say about 1025 - 1040mb. Yet the differential was also only about 10-25mb, so I don't know how it does this calculation, but it is clearly not BP - AP = differential pressure. There seems to be something else going on there and as yet I haven't figured it out.

Now for a Meteorology lesson:

Madrid at 667m above sea level means an average AP of 935mb at that altitude. But if you check the weather service it tells you the AP in Madrid is 1019mb (today). How can this be? Well the 1019 reading has been adjusted to sea-level, even though Madrid is a long way from the sea. So if you drilled a hole in the ground in Madrid 667m deep and took a reading down there you would get 1019mb. Meteorologists do this because if they didn't, their pressure isobar maps would just become terrain maps more or less. So the 1019mb reading is 6mb above average (1013), meaning the actual AP in Madrid is 935mb plus 6mb. I know it sounds stupid but there's no other way around it.

Finally a mention of swirl flaps.

I remain sceptical that swirl flaps in or out make much difference. Yes I agree that they aid combustion at certain revs, so if you remove them you have potentially less combustion in that rev range which equates to an increase in soot. But the question is, how much? I say sceptical but I have an open mind on it.

I found a little nugget on info recently on newTIS here which explains the flaps are open when intake air temps are less than 15C.
Explainer: Intake air temp is not the same outside air temp. It is outside air temp plus some heat from EGR gases, plus some heat from turbo compression of intake system, so generally a few degrees more than outside.

It is now mid October and in Ireland temps are about 15C midday, and my intake temps were around 16-24C today driving in the city. However there are some mornings when outside temps are under 10C already and the swirl flaps not active at all. They are fully open, through all revs. I have this swirl flap activation reading in Torque with custom PIDs. I should explain that my flaps were removed, but the car doesn't know this and still moves the actuator as if they are present.

As temps get colder going into winter and armed with this info I am guessing my swirl flaps would start to be inactive for most of winter. So they are effectively removed for a few months in cold weather. Obviously this will vary for hotter climates. Personally I won't be looking at putting them back in a hurry.

If you do want them back in then a cheaper alternative is https://pmgtechnik.com/en in Germany. They will send you a refurbished intake manifold they claim has better than original swirl flaps and when you remove your old manifold you send it to them. Not sure how shipping would fare from down under though tbh.

I could go on but this post is far too long already

All food for thought.

Keliuss
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  #139  
Old 10-12-2019, 01:28 AM
AU Pete AU Pete is offline
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Originally Posted by keliuss View Post

I could go on but this post is far too long already
Holy crap Keliuss! that is some amazing research and commitment to observations. Kudos to you

So my initial 2 thoughts are:

1) The PMGTechnik manifold reliability has a question mark on it - see mitocross's experience a few posts previous here ... i know thats only 1 data point - but it is what it is.

2) What would you do with my car? I'm not sure I want to drill any test holes in DPF walls or sensors! (but if the community consensus is drilling some holes I'm going to need some more detailed instructions - haha
(If there was a link to another specific thread with details on bmw5 there - let us know)

3) Given your research and the various factors going into the potential misreadings, Is there actually a downside to these regens that we think are overly frequent? Should we/i just ignore them?

Pete
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Last edited by AU Pete; 10-12-2019 at 01:59 AM.
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  #140  
Old 10-12-2019, 02:33 AM
keliuss keliuss is offline
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1. Swirl flaps are not an "open" or "closed" design. They are variable and are mostly at a partially open angle. They are designed to variably restrict flow on one of the two inlet ports, so will generally always let some air flow or "leak" by design. But don't take my word for it. Here is a snippet of a BMW training manual. I highlighted in yellow the relevant section.


They also single out the M57TU saying it's flaps close tight, which suggests that other variants don't.

Without knowing anything else about mitocross's manifold I am guessing here but perhaps the PMG flaps have a ridge or something which inadvertently causes a whistle.

2. Regarding my drill hole, as per GoNz0's suggestion you could just remove the rubber seal on the plug that goes onto the exhaust backpressure sensor for the same effect. I had a spare sensor, hence the hole.

If I was you I would try to gather more info around what your exhaust BP sensor is reporting and compare to ambient pressures.

I can see situations that would really mess things up for some people: If you lived at sea-level and worked somewhere at a higher altitude like in my examples. Only a few hundred meters altitude would result in your car calculating a high BP every day on your commute. Once a regen is triggered, it will want to complete, even if you commute back home to sea level.

Keliuss
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  #141  
Old 10-12-2019, 03:23 AM
keliuss keliuss is offline
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Originally Posted by AU Pete View Post
Holy crap Keliuss! that is some amazing research and commitment to observations. Kudos to you
I really should have mentioned that your own research and data logging was also excellent and a major help for my understanding of all the relevant info, so Kudos right back at ya

Keliuss
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  #142  
Old 10-12-2019, 08:07 AM
robnitro robnitro is offline
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Mein Auto: x5 35d e70 2011
Interesting back pressure analysis. With 35d usa there is a differential pressure sensor plumbed pre dpf and after dpf, so altitude would not affect that reading.


I think the flaps only actuate around very low loads, like idle or very light cruise. I'm confused why are they not used when cold and low flow because it's not restricting anything.
Maybe it's just to simplify cold running routines or prevent humidify icing up on the flaps which can cause them to break?

I remember someone from Finland had increased regen internal by refitting flaps...
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  #143  
Old 10-13-2019, 04:14 PM
AU Pete AU Pete is offline
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Mein Auto: 2007 X5 E70 3.0d
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Originally Posted by keliuss View Post
I really should have mentioned that your own research and data logging was also excellent and a major help for my understanding of all the relevant info, so Kudos right back at ya
ha - no worries. its been quite an international thread with help from all over. we should have an annual conference and meet somewhere to bury a few DPFs haha

Given your research and the various factors going into the potential misreadings, Is there actually a downside to these regens that we *think* are overly frequent? Should we/i just ignore them? (if the car is otherwise not throwing any errors that is - and just regenerating frequently).

i mean - its not ideal - but we're chasing our tails i think if we're ever going to fully correct this idea of a misreading driving frequent regens. whats the worst that can happen if ignore? im not sure the DPF is actually filling up with soot prematurely is it? its just having the captured soot baked to ash more frequently
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Last edited by AU Pete; 10-13-2019 at 04:21 PM.
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  #144  
Old 10-14-2019, 06:54 PM
robnitro robnitro is offline
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Mein Auto: x5 35d e70 2011
More soot more regens. That's it, waste of fuel and time to complete them.
They're determined by differential pressure on the dpf. There's a reason why they happen more often without flaps... How else would the dde know? Magic mind reading?
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