JayGee wrote:

No matter what the Workshop manual says a regen will stop prematurely if you brake or accelerate hard when it's part way through at least on my L322 as I've observed it with the GAP IID tool. It then just waits until it fills up again and reaches its soot limit rather than starting again to get the soot load down to minimum.

 2018 SE SDV8 4.4 Byron Blue

If that's the case, then there's something wrong with your cars software. I've never seen that on a JLR or any of the other half-dozen marques I've worked for at diag tech level or above.
Maybe the diag tool is acting as an intermediary and cancelling the regen?
I don't understand the obsession (for want of a better word) with monitoring regens when the vast majority of the population couldn't give the tiniest s t but in the main, it seems to transparently work for them.

I don’t watch dpf regenerations obsessively but was just curious to observe how it worked at one point on my car which may well be faulty or have been interfered with by the GAP IID tool but I’ve not had a DPF warning in >20k miles of ownership. 2012 TDV8 Vogue (L322)

Phoenix wrote:

I don't understand the obsession (for want of a better word) with monitoring regens when the vast majority of the population couldn't give the tiniest s t but in the main, it seems to transparently work for them.

Ha Ha I am one of those who does like to monitor Regens but wouldn't class it as obsessive.

It interest's me how the software works, utilising all the sensor inputs etc, would love to see the flow diagram! and when using my iPhone in a cradle with the sky scanner app, watching it live, it is interesting. I can monitor coolant temp, oil temp, def diff pressure, exhaust temps along the exhaust train also soot % Trigger point etc etc A lot more selectable inputs.
And I set an alarm at trigger 2 to let me know an AR has started.

Which is useful in preventing interrupted AR (engine stopped) which contribute to extra fuel dilution and reduces service miles.

Also I can see if an issue is developing with the dpf - where most people wouldn't know, till they get the dreaded Amber & Red etc
Horses for courses  2018 SE SDV8 4.4 Byron Blue

@K t - have you considered that the regen strategy on your L405 may not be identical to that on the L322 2012 TDV8 Vogue (L322)

I suppose because it's stuff I see at work, the novelty of seeing live values on a road test has worn - I do prefer to watch the traffic and surrounding countryside out of the car windows though, I don't think I'd like to be watching a phone screen whilst driving....
Things that will cause a regen to abort:-
Time taken exceeds maximum allowable time
No change in pressure differential over a programmed period of time
Fuel level drops below minimum programmed level
Engine speed / load constant in excess of programmed time limit
Exhaust temperature below minimum threshold
Engine switched off

In some cases, even seatbelt unfastened, aircon load too high and exhaust back pressure / boost pressure correlation can cause an abort - manufacturer dependent.

As with SCR faults, the cause is often a sensor value out of range, but not out of range enough to flag a DTC, under those circumstances, a test drive observing live values can be a great diagnostic aid. We do have someone else driving the car so as not to be distracted though.

JayGee wrote:

@K t - have you considered that the regen strategy on your L405 may not be identical to that on the L322

Yes unlike you I have looked at both WSM and their explanation, nowhere does it state the AR will stop if you brake or accelerate  2018 SE SDV8 4.4 Byron Blue

@K t -  2012 TDV8 Vogue (L322)

The active regen process can be actually seen clearly without any diagnostic tool by just observing instant fuel consumption - it is 4-5 l/100km higher than normal.

My L322 4.4TDV8 at least stops the active regen when speed decreases under 60 km/h. Not 100% sure about the acceleration, but I think it wouldn't interrupt it. I've been overtaking etc while in regen and it just keeps going, but when slowing down under 60 km/h, it always stops the regeneration.

Cheers
Keijo

Bloody Helpful post.

Get a diesel dpf car if you want one but just make sure you monitor soot levels up to 20 mg and then take for a 50 mph motorway run. That's how I've understood this Dpf malarkey.

I can't seem to get my IID tool to force a regen at all.

Had an air leak a while ago - DPF full yellow message. Sorted the air leak, but IID regen function did nothing (meeting all required thresholds with no error codes present). 'Luckily' when it reached 23g it started to regen by itself down to almost 0g.

Not had any issues in months, then yesterday - DPF yellow warning again. Turns out the same air leak at the throttle body - temp 'fixed' with some gas PTFE. Can't get the IID to force a regen once again. Still no error codes present at the time. Instantaneous MPG doesn't change and the soot levels don't drop.

Can anyone shed any light?

Hello All,
Yesterday my dpf was cleaned again, by the same company that cleaned it on July 2019 (page 13, posted at July 12, 2019)
The reason to do it now was a single amber warning about 3 weeks ago that went away after a regeneration drive - I watched the instantaneous fuel consumption go up for 10 minutes and go down to normal, somewhere half way the warning cleared by itself and didn't come back.
After only 81000km this time, including 4 trips to the Polar Circle in winter with several cold morning starts around -20C and some cold engine idling too while digging the car out of the snow.
The weight test showed they removed 150 gram of stuff/ash/soot.
A pressure difference test showed it went from 82mbar back to 5mbar.

The people in the workshop said this OEM dpf filter can be cleaned as long as the car drives.
The coating in the OEM dpf is durable and won't get damaged by regenerating or cleaning.

There is a slightly better throttle response.

The first time after 132857km it had 70 gram of dirt, this means 0,527 gram / 1000km.
Now after 80887km this has more than tripled (!) to 1,854 gram / 1000km.

Could this increase be an indication of something?
Oil from the secondary turbo?
Or was it the idling in the cold? 2012 4.4TDV8
2000 Honda S2000

Did they clean it by removing it from the vehicle and back flushing the ash out? 150g seems not very much TBH. 2012 TDV8 Vogue (L322)

If the amber light went off after a natural regeneration on a run then why have it cleaned? It’s working as it should or am I missing something? 2011 4.4 TDV8 Vogue SE Buckingham Blue with Ivory and clear glass = "Rory"
New Defender D300 90 on order so "Rory" will be going to a new home....!
1974 Series 3 Lightweight = "Millie"
My preferred specialist: www.glenrands.co.uk
--------------------------------------------------

The first time I went there, in 2019, they cut the exhaust at 2 points based on images I found on this forum (I'm not sure it was in this post).
They remove that part and put it in their machine to clean it.
The company is Advanpure.
https://advanpure.com/en/

They weigh it before and after.
The same with the back pressure test.

70g or 150g of ash doesn't seem much, I agree.
It doubled during the last 80000km though.
Does anyone have real world numbers of how much the OEM dpf can hold?

Yes, it was working as it should.
Now that it's cleaned it's working even better
Seriously: in the last 4 years I didn't see any warning light.
I've noticed at times it was regenerating during my short evening commute as you can smell it when parked, I park in a semi closed small parking garage.
So when the amber warning showed up 3 weeks ago I just though it was time to go for a proper cleaning.
edit:
The first time this happened to me, in 2019 with the amber and red warning, they removed only 70 gram of ash.
This time it was 150gram.
Why didn't I see anything 40000km ago?
Maybe it gathered 100 gram in the last month?
Maybe the ECU also has a miles/time log or algorithm running to generate amber/red warnings?

Maybe it partially pays for itself by less fuel consumption, diesel isn't cheap.

We change oil filters, air filters, fuel filters... why not clean dp filters?
Btw, I clean my ITG air filters too, when needed.
 2012 4.4TDV8
2000 Honda S2000