Help please with DPF regen

[V12noise]

M57 35D

Had the Particle Filter warning on the Dash, so looked at the fault memory with ISTA+ and saw the relevant errors were 480A and 481A.

Did the pressure tests at idle and 2000rpm and found the pressures to be just under and just over the thresholds, respectively. Last regen was around 3500km ago and a whole lot longer before that - probably due to faulty thermostat.

From various threads and youtube, worked out I had to delete the Fault memory and then request a regen. This appeared successful and the ISTA status page said Regen Enabled and while I drove RegenStatus went between InActive and Active for a while, and then stayed Inactive.

The final transition to inactive was at around 10 mins after clearing the fault memory and I guess the 480A error had come back. When I looked at the fault memory again, sure enough the 480A was there.

The question then is how to get through this? Do I need to make sure I don't get inactive before the regen is complete? I guess I need to delete the fault memory and request the regen just before getting onto the motorway...?

[V12noise]

Anyone can help?

[TriX5]

Somebody on XO did a complicated trick to make the diff pressure sensor read just the right amount to allow the DPF to regenerate but still haven't found the thread. Will post a link if and when I find it.

EDIT: It was Zeta Tre in this thread:

https://xoutpost.com/bmw-sav-forums/...-diy-pics.html

He said this:

"""As I stated elsewhere this whole thing started after my dad has been battling with failed glowplugs and clogged DPF. The root cause of it all was the engine not maintaining normal operating temperature (defined as >75C) resulting in running in warmup mode (i.e. overfueling and glow plugs under light to medium load) and failing to carry out regular DPF regen. Restarting the regen was a bit more tricky since it required fooling the DDE in reading lower backpressure which we resolved using the hose with a slit."""

He described the process more extensively elsewhere but I couldn't find that thread.

[V12noise]

Update:
Did some research on the internet and people described BimmerTool App as doing continuous Clear Fault Memory commands while regen is active. Downloaded App for £13.99 as it works with my existing ELM327 Bluetooth adapter.

Set it up for a forced Regen, which it did, but after a few minutes it fell out of Regen. Dont know why. Re-set it to Regen and this time it did it for approx 20 mins.

My notes on the Regen process are:
1) If there are Regen relevant Fault memory errors, the ECU will block a Regen, no matter how hard you drive.
2) Exhaust temp rises quite quickly to >240°C, so you dont need to drive too hard. Once regen is started, exhaust temp rises to around 600°C and it looks like the ECU tries to regulate it there. Of course if you release the accel pedal, temp drops. Soot value decreases quicker if you can maintain >500°C exhaust temp.
3) Regen started at 60°C water temp. I've seen, BMW documentation saying it starts above 75°C but I guess they've reduced this to make it easier...
4) Regen is independent of car speed. I even did a 3-point turn at one stage and Regen remained active.
5) Regen went inactive a couple of times for no reason. Re-enabled it and it all seemed to work again. Just shows the importance of monitoring systems - without them you're blind.
6) INSTA+ is actually not that good for Forced Regen as it requires power cycles to clear Fault Memory and to set Forced Regen. So how come BimmerTool does both with the car and engine running??? Also I couldnt find a way to monitor the temps as well as the the Regen Active state on Insta+
7) Soot level goes down during the Regen but this is a Simulated value. It will go down to 0 grams for a successful complete regen, but it soon rises after Regen. Mine went back up to around 25g within a few minutes. Out of Regen, the soot value is 'real' albeit a function of DPF differential pressure.
8) After the successful regen, I did a counter pressure test and the idle value was approx 20mBar. A bit high I thought although under the limit, so I repeated the Forced Regen. The 25g of 'real' soot minutes after Regen and the 20mBar at idle didnt change. So concluded this is a function of an aging DPF. My Ash value is suspiciously low at 18g, so I guess one of the previous owners did a new DPF procedure somewhere along the line in a bid to cure a DPF issue....
9) In another forum, someone noted an ECU value for soot production which is around 1mg per second. so 1g in 1000 seconds and the DPF capacity of 60g in 60,000 seconds or 16,6 hours of driving. If the DPF is half full then every 8 hours... kinda makes sense as that is approx 240miles at 30mph. Of course soot values will vary. But it just shows that it doesn't take long for a healthy car to suddenly start posting terminal particle filter messages when something starts to go wrong....

I hope this helps someone... there is a lot of drivel being written about DPF regen and a lot of people pulling their hair out - including me until I worked it out...

[Bluefish7]

I can clear 480A and 481A but I guess they're coming back too quick for regen to start

[V12noise]

An update:

First the good news - the ECU started its own DPF regen during a drive...
Then the bad news - it was just 54km after the previous regen...

I was driving around with BimmerTool connected. Exhaust temp around 350°C and Water temp 90°c. Soot rose quickly from 25g and at 50g the ECU began a regen which completed successfully some time later. Then after just a few kms, soot was back up to 40g.

My thoughts...
1) Soot mass is a function of DPF exhaust pressure so either the DPF is truly blocked or the Pressure sensor is reading falsely. Or there is a problem with the interconnecting hose. Looking at the BMW parts diagram, it is not a differential sensor so unlikely the hose is a problem as a leak would decrease the pressure.
2) I deleted the Swirl Flaps a few thousand miles ago, so I'll re-instate them to rule them out...
3) Car has a power-tune mod by the previous owner. I don't know how much that is contributing.

Next steps...
1) Vacuum hoses replacement was on the cards so I'll do that at the same time as replacing the swirl-flaps. I'll also change the pressure sensor.
2) I'll replace the DPF if the hoses and pressure sensor replacement doesn't work...

[TriX5]

Unless your 2010 is different (your location seems to indicate that you have a Euro spec version), on my '09 there were two sensors mounted on the passenger side of the engine, where the vac reservoir lives. One is a diff pressure sensor monitoring the DPF (the folks who cleaned my DPF replaced the hoses). The other is a pressure sensor monitoring the exhaust manifold (the hose connected to it leaked on mine and I replaced the pipe/hose combo). The DDE reads both and detects if they are behaving out of line with expected values.

[V12noise]

Originally Posted by TriX5

Unless your 2010 is different (your location seems to indicate that you have a Euro spec version), on my '09 there were two sensors mounted on the passenger side of the engine, where the vac reservoir lives. One is a diff pressure sensor monitoring the DPF (the folks who cleaned my DPF replaced the hoses). The other is a pressure sensor monitoring the exhaust manifold (the hose connected to it leaked on mine and I replaced the pipe/hose combo). The DDE reads both and detects if they are behaving out of line with expected values.

I'm not getting any errors relating to engine at the moment. My parts diagram shows a single channel pressure sensor, so I'm guessing it is relative to one of the other exhaust pressure sensors. Static reading is 0.9 mbar with the engine off, so maybe the sensor is ok.

I'm waiting for the bits to arrive before steaming in to the vacuum lines and sensors....

[TriX5]

Ah, yes, your system seems different from mine.

By the way, possibly for a few hundred Euro somebody can clean your DPF rather than replace it? I had mine done in the NL by a specialist who were quite familiar with it. Also, I know in Germany there are companies providing refurbished DPF replacements (you can order and send yours back to get core charge refunded). A new DPF runs in the thousands......

[V12noise]

Originally Posted by TriX5

Ah, yes, your system seems different from mine.

By the way, possibly for a few hundred Euro somebody can clean your DPF rather than replace it? I had mine done in the NL by a specialist who were quite familiar with it. Also, I know in Germany there are companies providing refurbished DPF replacements (you can order and send yours back to get core charge refunded). A new DPF runs in the thousands......

I was thinking along the same lines... I bought one from ebay for €189 which is dirt cheap compared to the €2000 bmw want. It may or may not work but it'll give me a chance to get the original one cleaned...