Page 1 of 2

How often does the DPF do a burn ??

Posted: Wed Oct 31, 2018 8:38 pm
by Fireguard
Has anyone actually noticed how often the DPF does a burn ?

Now thinking purely "hypothetically" :roll: in a remapped engine, could the ECU be programmed to conduct burns more frequently than what would be normal ??? (thinking maybe, less chance for build-up so less restriction = more power etc)

Re: How often does the DPF do a burn ??

Posted: Thu Nov 01, 2018 10:56 am
by RossPat
I don't think there is a set time, it burns off when the Soot reaches a certain level.

I have mine monitored and when it reaches 100% it does a burn, temp climbs to over 600c

Burn time and distance varies depending on the driving conditions.

Stewart will let you know if it can be programmed to burn off.

Re: How often does the DPF do a burn ??

Posted: Thu Nov 01, 2018 10:05 pm
by saeb
Seen reference to manual burn off some where in programming, it may have been in the PCM.

Never bothered looking any further for a manual burn as I do not have one and the assumption would be if it was available it would be enabled and controlled by the instrument cluster. Then again maybe I saw it in the disassembled cluster firmware and not the PCM.

Basically at this point in time I see no easy option to enable a manual burn nor change when the burn off occurs without modifying the PCM firmware, and I'm sure the vehicle is more than smart enough to do what it has to do with balancing fuel economy vs power.

I would say more burn off would mean higher fuel usage.

All it apears to do it use 2 pressure sensors on the DPF and when the difference between the 2 = X then a burn off occurs under the correct conditions. It would be more than plausible to trick one sensor to read higher than it really is to initiate a burn but as above I do not have one so have nothing to test it on.

Re: How often does the DPF do a burn ??

Posted: Fri Nov 02, 2018 1:02 pm
by Fireguard
Since I've been monitoring my EGT temp, I've noticed what looks like a dpf burn happening relatively frequently...

Just wondering if it's normal, or BPT.

Re: How often does the DPF do a burn ??

Posted: Fri Nov 02, 2018 3:03 pm
by RossPat
Which if any would be the correct one/s to monitor for burn off?

Re: How often does the DPF do a burn ??

Posted: Fri Nov 02, 2018 4:44 pm
by GerryP
None of the above Ross, you need EGT13 which will show you post turbo EGT and will go over 600 uring a burn.

Here's the OBDLink codes...
Description: EGT
English Units: psi
Min Value: 0
Max Value: 1000
Metric to English Scale Factor: 1
Metric to English Offset: 0
Module /Header: 7E0
OBD Mode: 22
PID No: 03F6
Priority: High
Equation: A*5

Re: How often does the DPF do a burn ??

Posted: Fri Nov 02, 2018 5:49 pm
by RossPat
Thank you very much Gerry, much appreciated.

Re: How often does the DPF do a burn ??

Posted: Fri Nov 02, 2018 7:45 pm
by GerryP
RossPat wrote: Fri Nov 02, 2018 5:49 pm Thank you very much Gerry, much appreciated.
You're welcome mate, but I need to acknowledge Stewart for the OBDLink conversion. :)

Re: How often does the DPF do a burn ??

Posted: Fri Nov 02, 2018 8:00 pm
by RossPat
GerryP wrote: Fri Nov 02, 2018 7:45 pmbut I need to acknowledge Stewart for the OBDLink conversion. :)
We all have to do that mate :D :D

Re: How often does the DPF do a burn ??

Posted: Wed Nov 07, 2018 8:22 am
by RossPat
Hey Gerry.
In Arno Bay exercising the Ranger in sand, earning it's keep alright.

On the way over @ 105kph the DPF temp was sitting around 340 to 360.

As I have Celsius as my set up setting is that about right, compared to yours.

It climbs higher when working in sand but that is expected.

That temperature would explain why it away seems warm driving the Ranger and even in 4deg temp I don't need heaters on.

Re: How often does the DPF do a burn ??

Posted: Wed Nov 07, 2018 9:34 am
by GerryP
That's about right Ross and similar to what I usually see. Not sure how that would affect cabin temp though?

Re: How often does the DPF do a burn ??

Posted: Wed Nov 07, 2018 9:58 am
by RossPat
I thought all that constant heat blowing onto the firewall is causing it, if not I don't know what else would make it so warm.

Re: How often does the DPF do a burn ??

Posted: Sun Mar 31, 2019 6:15 pm
by GE350
Just following up on this thread, I am noticing the DPF burn today occured 4 times in under a 4 hour drive!!

This seems excessive, I am confident it is right as the EGT hit over 600, the boost pressure drops and fuel usage increased.

What i want to know is there a code to adjust the differential? I am running a 3" straight from the DPF which would actually drop temps of the final probe

At this stage i will leave the DPF fitted but want to adjust frequency

any help appreciated on the exact circumstance the vehicle determines a burn

Re: How often does the DPF do a burn ??

Posted: Wed Sep 04, 2019 7:35 pm
by saeb
GE350 wrote: Sun Mar 31, 2019 6:15 pm Just following up on this thread, I am noticing the DPF burn today occured 4 times in under a 4 hour drive!!

This seems excessive, I am confident it is right as the EGT hit over 600, the boost pressure drops and fuel usage increased.

What i want to know is there a code to adjust the differential? I am running a 3" straight from the DPF which would actually drop temps of the final probe

At this stage i will leave the DPF fitted but want to adjust frequency

any help appreciated on the exact circumstance the vehicle determines a burn
Back pressure. There are 2 sensors, one each side of the DPF that measure pressure difference. Keep in mind a previous burn may not complete and a full burn can take up to 50 minutes but may have paused to your driving conditions at the time.

Re: How often does the DPF do a burn ??

Posted: Wed Sep 04, 2019 9:04 pm
by RossPat
My Average burn distance & time
Ignore tyre pressures, not moved the car in 5 days
mon1.jpg
mon1.jpg (2.25 MiB) Viewed 540 times
mon1.jpg
mon1.jpg (2.25 MiB) Viewed 540 times

Re: How often does the DPF do a burn ??

Posted: Fri Sep 06, 2019 12:48 am
by blueshine
Mine is showing an average DPF distance of around 220km and 350 min. This is probably because most of our journeys are around 20-30 mins.

The DPF soot% seems to count up fairly linearly, approximately 1% per 4km in our case, then when it hits 100% it starts a burn and then gradually reduces the soot% back down. I've noticed that if it starts a burn shortly before you arrive at your destination/turn the car off then the burn is incomplete and the soot% is only slightly reduced. However the next time you start the car it forgets about the previous burn, sees the new soot% as under 100% and then runs normally counting up again.

Given this it's possible to get into a very short and frequent burn cycle. eg. I did an 80km round trip for a few days, it would start from about 80% and then initiate the burn a few minutes from home, by the time I'd arrived it was down to about 80% again. The next day it would start from 80% and then hit the burn point just before I arrived home, and would do the same again. Certainly it seems if you had a regular commute of certain lengths it could be possible to get into a cycle of very short and frequent burns.

Something else I note is that contrary to what I've read about having to do constant or highway speeds during a burn, it's happy to burn around town in traffic and seems to work fine at idle without any obvious difference in idle rpm. Hopefully it doesn't develop any faults in the years to come, but it if carries on like this then the DPF is really a non-issue and preferable to the alternative of pumping crap into the air we breathe.

Re: How often does the DPF do a burn ??

Posted: Fri Oct 11, 2019 1:24 pm
by GE350
What reference in Forscan for soot count?

Re: How often does the DPF do a burn ??

Posted: Fri Oct 11, 2019 2:33 pm
by RossPat
Mine is done with the OBDLink app and dongle

Re: How often does the DPF do a burn ??

Posted: Wed Feb 05, 2020 7:05 pm
by GE350
My average kms between burns shows as 416km, pretty bloody often. My last burn was 456 according to forescan

Re: How often does the DPF do a burn ??

Posted: Wed Feb 05, 2020 8:42 pm
by RossPat
GE350 wrote: Wed Feb 05, 2020 7:05 pm My average kms between burns shows as 416km, pretty bloody often. My last burn was 456 according to forescan
Shorter runs with stop/start driving will have a shorter burn cycle/time.

Re: How often does the DPF do a burn ??

Posted: Fri Feb 07, 2020 1:31 pm
by baza32000
My 2lt burns every 200 - 300km. Must be a small unit, our Jeep burns every 600 - 800km.

Re: How often does the DPF do a burn ??

Posted: Fri Feb 07, 2020 7:56 pm
by tugsay
I'm using static regenaration on winter time because of tha cold weather, I think it can not finish the regen cycle itself. I disabled the egr and remapped the pcm and that causes dpf to clogged much frequent.

Is doing static regen have any harm for the engine or the injectors or anything else except the normal wear of the engine for running 2000rpm for a certain amount of time.
I don't want to disable the dpf or wait for it to death by itself because of the remmaped engine and disabling the egr.

Re: How often does the DPF do a burn ??

Posted: Fri Feb 07, 2020 8:30 pm
by RossPat
I have been told a static regen is not good for the engine and should be avoided.
If you have to do a static regen the engine oil should be changed afterwards.

Re: How often does the DPF do a burn ??

Posted: Fri Feb 07, 2020 9:34 pm
by tugsay
Ok, thats not good in my situation. I should drive the car on highway on high speeds more often than.
Thanks RossPat...

Re: How often does the DPF do a burn ??

Posted: Mon Feb 24, 2020 10:51 pm
by TieNN89
Just enabled the DPF Gauge on my Ranger and now have a question.
How far down does your DPF burn to?

Mine went from 80% and to 95% this morning going to work. (15mins 80km/h)
Then when leaving work it got to 99% (within 5 mins) then down to 20% (11mins 100km/h)
But I had to get off the highway for 5 mins. Got back onto the highway and it starting getting back up to 35% before I switched the car off (13mins 100km/h)
Only switched the car off to about 10mins, got back onto the highway to head home and it went to 45% (15mins mostly 100km/h)

Does it sound right to only get down to 20%? I feel like it should get to 0%.
And it also feels like it goes up quick too.