DPF always goes up to 100 percent before starting regen

[brianzoh]

I guess I really don't understand why this is a big deal at all. There is no warning light because there is no error condition. The onboard computer manages regen completely without user intervention and has been built to compensate for all the things that might happen such as interrupting the regen, idling, engine temp, etc. The logic programmed into the process accounts for things that, as a driver, you'll never even know such as engine speed avg, load, etc.

 

[Deleted member 50714]

I guess I really don't understand why this is a big deal at all. There is no warning light because there is no error condition. The onboard computer manages regen completely without user intervention and has been built to compensate for all the things that might happen such as interrupting the regen, idling, engine temp, etc. The logic programmed into the process accounts for things that, as a driver, you'll never even know such as engine speed avg, load, etc.

My experience 2015, OM651. I, unknowing interrupted regenerations three times and it threw a CEL, code P2459.

Repeated DPF regeneration interruptions may result in a "hard" limp home mode cleared only by dealer level or equivalent diagnostics. .

Fortunately for me, after driving the vehicle for a couple hundred highway miles, OBD (Onboard Diagnostics) self-extinguished the CEL.

 

[Old Man]

It is a simple mistake that can be easily understood...

1 mile = 1.6km

300 miles x 1.6 = 480km

So it should have been stated "300 miles" and "480km"

Given what is being said above "regen at 500 miles" that would be 800 km.

I would be interested to hear from someone in a "km" van if that is the case.

 

[elemental]

I guess I really don't understand why this is a big deal at all. There is no warning light because there is no error condition. The onboard computer manages regen completely without user intervention and has been built to compensate for all the things that might happen such as interrupting the regen, idling, engine temp, etc. The logic programmed into the process accounts for things that, as a driver, you'll never even know such as engine speed avg, load, etc.

Sure - it's all fine and works peachy for some. But - I've been to dealers' workshops 4 times already with only 20,000 miles on my van; 3 times due to the check engine light being on, and once because the regeneration cycles were happening about twice as fast as they were supposed to. All four visits were over problems with how the DPF system was functioning (or not), with me being criticized on two of the visits for too many interrupted regenerations (and you can't tell whether you are interrupting a regeneration without a regeneration indicator).

The system is supposed to work the way you have described. And for some number of people it does, according to anecdotal evidence on the forum. But for others, it doesn't. And the system and its programming is suspect, in my book. The second visit included getting new software loaded, but it didn't make things obviously better. At the third visit a regeneration report handed to me by a technician showed that every single regeneration attempt over about 10,000 miles of driving, mostly highway, had been ended by "key off" (i.e., I shut the van off and interrupted each and every regeneration cycle (all sixteen or so of them). (I keep a hand log of the regenerations I become aware of through my ScanGauge II now, which is why I could tell that the regens started occurring at twice the expected rate. The fix for that was a manual regeneration, after the tech informed me that the system has been initiating regenerations more frequently because (surprise!) none of the regenerations were completing properly [key off events showed in the on-board log] despite my monitoring carefully and always making sure that I kept driving the van until it had stopped regeneration itself.

Regeneration isn't an error condition - neither is having your high beams on. But an indicator light is a useful thing to help the operator understand what the vehicle is doing, especially when that knowledge aids in effective operation. And since the regeneration system is touchy, it aids in diagnosing problems.

I still like my van, and I plan to keep it a good long while. But the DPF system is not its best feature.

 

[220817a]

Given what is being said above "regen at 500 miles" that would be 800 km.

I would be interested to hear from someone in a "km" van if that is the case.

The mistake is happened and comes from the 2019 Owner's manual... See the 3 images below... 2018 2019 and 2020.

 

[220817a]

I guess I really don't understand why this is a big deal at all. There is no warning light because there is no error condition. The onboard computer manages regen completely without user intervention and has been built to compensate for all the things that might happen such as interrupting the regen, idling, engine temp, etc. The logic programmed into the process accounts for things that, as a driver, you'll never even know such as engine speed avg, load, etc.

To you it might not be a big deal, but for some people it is important to monitor the regen cycles because it can give them a heads up/warning of a potential problem with the DPF system before the warning light comes on. Simple as that... Nothing really complicated to understand.

 

[MTGJR1]

Continuing my "determining normal" data collection. Typically, % load doesn't decrease unless system is going through regen (goes from 100% to 0%). Yesterday on a road trip, started at 72% (after documenting 76% at the end of previous trip), slowly dropped to 68% during first 15 miles highway travel at 70mph, then started its increase again.

I have high confidence previous end at 76% was not an interrupted regen cycle.

 

[elemental]

My DPF% (monitored with ScanGauge) has sometimes decreased while driving without the van being in regeneration mode (also monitored with the ScanGauge). The occasional spontaneous reductions are small (single digits, possibly as much as ten or so points) and don't look at all like the steady decreasing from 100 (or 103!)% down to 0% to 3% over ten to fifteen minutes that I see for a regeneration cycle. I haven't kept close enough track to know whether the DPF% on a new start is lower then the DPF% at the previous stop, but I wouldn't be surprised at that either.

 

[DSM]

Interesting topic since I just found the load screen yesterday while looking for my tire pressure screen.
I googled it to learn what it was and then called the dealer to discuss.
My trips are normally 30-125 miles between stops. Not much city driving in 2500 miles since new. I have had some short start/stop cycles to move the van in and out of the garage during the conversion process.
My call to the dealer to discuss this only resulted in more confusion since I was on the road, traveling 60mph and watching the load climb from 64% to 74% in 20 miles.
The service writers initial reaction was surprise over the low overall miles and recent long trips with 2 hours at around 70mph on each of four legs.
Next the service writer consulted a tech who said not to worry about it unless it had not self regenerated by the time it reached 200%.
Sorry.. what? The dash symbol is near full?
And now that I drove an hour home it was at 98%.
The tech said they could manually activate the regen with their MB diagnostic computer at any time if it became a problem.
I’d like to know:
-will it autoregen at 100%? Dealer could not tell me.
-Do I need to plan an additional trip around this so I don’t interrupt the cycle?

It would be more convenient if the owner could perform the regen during a planned trip. And, as mentioned by others, it would be helpful to know when to perform or when the process has initiated so the operation is not interrupted.

 

[Deleted member 50714]

DSM, thank for sharing. This is an interesting topic for me.

May I make a few suggestions?

First, you got to figure-out a way to determine when DPF is regenerating and avoid interrupting the process.

On my 2015 four-cylinder, I use a Scan Gauge and they occur about every 550 miles and last about 15 minutes. At which time I reset one of the trip meters on my ODO and begin monitoring mileage in anticipation of the next regeneration to hopefully coincide with uninterrupted highway driving or my next oil change performed afterwards.

During regenerations maintain , at minimum, 2200 RPM recommended by manufacture, and possibly the rpm required to initiate post fuel injections to elevate DPF temperature to 1100+ degrees F.

That's the first step.

Also, be aware, there are manufacturer's prerequisites before performing DPF regenerations and not intended to performed willy-nilly, and probably why owner feature not provided. Regenerations increase fuel injections and the possibility of crank case oil contamination.

Once your last DPF regeneration has be determined, only then you can use your On Board display to get a better feel about DPF fill-level percentages.

Also understand, the DPF fill percentages displayed are based on algorithms and performance maps research and not actual DPF fill level.

Meanwhile, I suggest reading the maintenance book and it's guidance on how to operate the vehicle. Particularly shifting in city driving. Got to keep those rpms up!

 

[Deleted member 50714]

DSM, thank for sharing. This is an interesting topic for me.

May I make a few suggestions?

First, you got to figure-out a way to determine when DPF is regenerating and avoid interrupting the process.

On my 2015 four-cylinder, I use a Scan Gauge and they occur about every 550 miles and last about 15 minutes. At which time I reset one of the trip meters on my ODO and begin monitoring mileage in anticipation of the next regeneration to hopefully coincide with uninterrupted highway driving or my next oil change performed afterwards.

During regenerations maintain , at minimum, 2200 RPM recommended by manufacture, and possibly the rpm required to initiate post fuel injections to elevate DPF temperature to 1100+ degrees F.

That's the first step.

Also, be aware, there are manufacturer's prerequisites before performing DPF regenerations and not intended to performed willy-nilly, and probably why owner feature not provided. Regenerations increase fuel injections and the possibility of crank case oil contamination.

Once your last DPF regeneration has be determined, only then you can use your On Board display to get a better feel about DPF fill-level percentages.

Also understand, the DPF fill percentages displayed are based on algorithms and performance maps research and not actual DPF fill level.

Meanwhile, I suggest reading the maintenance book and it's guidance on how to operate the vehicle. Particularly shifting in city driving. Got to keep those rpms up!

SUPPLEMENTAL:

DSM, thank for sharing. This is an interesting topic for me.

May I make a few suggestions?

First, you got to figure-out a way to determine when DPF is regenerating and avoid interrupting the process.

On my 2015 four-cylinder, I use a Scan Gauge and they occur about every 550 miles and last about 15 minutes. At which time I reset one of the trip meters on my ODO and begin monitoring mileage in anticipation of the next regeneration to hopefully coincide with uninterrupted highway driving or my next oil change performed afterwards.

During regenerations maintain , at minimum, 2200 RPM recommended by manufacture, and possibly the rpm required to initiate post fuel injections to elevate DPF temperature to 1100+ degrees F.

That's the first step.

Also, be aware, there are manufacturer's prerequisites before performing DPF regenerations and not intended to performed willy-nilly, and probably why owner feature not provided. Regenerations increase fuel injections and the possibility of crank case oil contamination.

Once your last DPF regeneration has be determined, only then you can use your On Board display to get a better feel about DPF fill-level percentages.

Also understand, the DPF fill percentages displayed are based on algorithms and performance maps research and may not reflect actual DPF fill level.

Meanwhile, I suggest reading the maintenance book and it's guidance on how to operate the vehicle. Particularly shifting in city driving. Got to keep those rpms up!

 

[Kajtek1]

MyOM651 cruise at 2000 rpm most of the time.

 

[Deleted member 50714]

MyOM651 cruise at 2000 rpm most of the time.

I'm thinking that's a good cruising rpm .

 

[Deleted member 50714]

CJPJ posted a chart showing DPF begins passive regeneration about 550°F and target I try to shoot for.

 

[Kajtek1]

I'm thinking that's a good cruising rpm .

My Ford truck was cruising at 1600 rpm and with 5000 lb camper it would not downshift till bigger than 6% grade.
But the point is that how you want to keep above 2200 rpm, when cruising rpm is 2000 ?