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Dieselhawk
08-13-2013, 02:12 PM
Hi Guys,
I have a 2008 311CDI with approx. 110,000km on the clock. Its never missed a beat up until last week when I noticed a miss on hard acceleration and it stalled twice, funnily enough both times as I pulled into the Mercedes dealer to pick up parts for another vehicle (I am a diesel mechanic myself). I noticed it was down on power and it brought the check engine light on. It slowly got worse over a day or so until I took off the next morning and it was totally gutless to the point that I had to pull over and get towed. It now had the check engine light flashing. I replaced the fuel filter but made no difference.
It has now been in the Merc dealer for 4 days. I decided to take it straight there as I didn't have the software required or anything that would read the codes. I work on bigger stuff Detroit, Cat, Cummins etc
First I was told the only relevant stored code was low boost or similar.
They thought I had put biodiesel or some poor quality diesel in (which I hadn't) so they replaced the fuel in the tank but this made no difference.
When I called this morning they now tell me the only active code is relating to the DPF but this wouldn't cause the problem. This sounded a bit funny to me so I did a quick search and found this

Below are some of the most common problems when the dpf fails on a Mercedes Sprinter.
Loss of power / no throttle response
Engine/DPF warning lights on dash
Poor fuel consumption
Hard to start and slow pickup speed
Limp mode (wont rev over 3000rpm)
Engine starts and cuts out
Engine fails to starts

I have all these symptoms bar the poor economy and failing to start. Since then they disconnected the DPF and the engine now runs fine in the shop. But they still say they don't know if its the DPF or Cat so are removing one off another vehicle to try it.
Now it doesn't look like "rocket surgery" to me but I just wanted a few opinions before I go in with a tilt tray tomorrow and drag the thing back to my own workshop.
I have asked twice for the price on a new DPF but they are reluctant to give it to me. I have found a local company that clean them so will probably go with that.
The bill for 4 days of scratching their heads/nuts will be the next hurdle.:yell:

Cheers, any advice or comments much appreciated.

PS Currently downloading diagnosis software so this never has to happen again!

parcelpeter
08-13-2013, 03:31 PM
Get them to try a regeneration on the dpf with the computer or try to regenerate it yourself by driving on a dual carriage-way or motorway for 20-45 mins in 4th gear at 2000RPM to initiate a regeneration.You will know its regenerating by the smoke.
Ive had mine deleted cause of the work i do with the van,start stop all the time and dpfs hate that.

Dieselhawk
08-13-2013, 11:22 PM
Thanks parcelpeter,
The van won't even run with the DPF connected at the moment but they might be able to do it in the shop. I'll ask the question. Cheers.

lindenengineering
08-14-2013, 03:36 PM
Talking about these filters I have just taken one off a TOTALLY plugged up 2008 CRD.

Not only is the induction and EGR side blocked up with carbon but so is the exhaust!
AND this was driven from "Nu Joisey" to Denver!:hmmm: Persistant owner for sure!:laughing:

Well I did fling it to a guy who cleans these things in Denver but he couldn't get it totally clean. So its going to be a new one. Ouchie!

Anyway if yours needs cleaning AND its not totally plugged up and beyond redemption then sent it to Riley @Intermountain Radiator And Muffler tel; 720, 581, 5004.

Dennis

lindenengineering
08-14-2013, 04:08 PM
Post Addendum
Just so you folks are wondering JUST how much is a DPF filter; $2690 is the quote from MB here in Denver----Just beer money I suppose!:idunno:
Dennis

gottahavabenz
08-14-2013, 04:28 PM
Dennis

How much is Riley to clean it? Ballpark on a 75% plugged unit.

lindenengineering
08-15-2013, 12:30 AM
His standard charge is $300.
That stated it wasn't successful on the bad boy I gave him on Monday, he could only get it 50% cleaned so it was $150.

Dennis

BBlessing
08-15-2013, 02:25 AM
this tale is cause to keep your foot out of the throttle. drive them as easy as possible to keep this type of thing from happening.

bb

sailquik
08-15-2013, 02:36 AM
BBlessing,
My experience with NCV3's with DPF (granted they were 2010 or later Mercedes Benz, not Dodge or Freightliner) is pretty much the opposite.
Keep some revs on them >2400 for sure, and a few times per day "blow them out" with heavy acceleration to get the temps up and revs over 3000.
Works for me!
Roger

BBlessing
08-15-2013, 04:24 AM
Bill,
My experience with NCV3's with DPF (granted they were 2010 or later Mercedes Benz, not Dodge or Freightliner) is pretty much the opposite.
Keep some revs on them >2400 for sure, and a few times per day "blow them out" with heavy acceleration to get the temps up and revs over 3000.
Works for me!
Roger

I don't know who bill is. anyhow, what I was getting at, is that putting your foot in it at low rpms is what is plugging up the dpf. yes high rpm driving is good for clearing out things, but it is good or better to get there gently.

bruce blessing

CJPJ
08-15-2013, 06:23 AM
and a few times per day "blow them out" with heavy acceleration to get the temps up
Works for me!
Roger Heavy acceleration produces more soot and is Counter productive to unblocking a DPF! "heavy acceleration to get the temps up" Not needed! Regenerations will start fine with 40 miles per hour exhaust temperatures, then the engine management will increase exhaust temperature through late fuel injection.

If you ever watched the exhaust stack of a pre 2007 diesel , pre being before Diesel partial Filters. They belch soot. A lot of the time it's noticeable when the operator has there foot in it going through the RPM's accelerating. Once up to speed the exhaust clears up. Black soot collects in the DPF and is filling it until the soot triggers a regeneration. The regeneration cleans the DPF but not 100% eventually the filter dies. So driving around avoiding the heavy soot instances has got to extend the time duration between the regenerations and extend the life of the DPF.
anyhow, what I was getting at, is that putting your foot in it at low rpms is what is plugging up the dpf. yes high rpm driving is good for clearing out things, but it is good or better to get there gently.

bruce blessing

X 2

shanemac
08-15-2013, 07:10 AM
Is there a low tech easy way to tell if the DPF is starting to plug without pulling the DPF off, is there a metric/baseline of exhaust air flow out tail pipe at idle?

dukepilot
08-15-2013, 07:27 AM
Is there a low tech easy way to tell if the DPF is starting to plug without pulling the DPF off, is there a metric/baseline of exhaust air flow out tail pipe at idle?

Not low tech but you can read/monitor exhaust pressure differential at the DPF with a good scan tool (MB Star, Diagun, AutoEnginuity w/enhanced package). What's missing are the numbers/values that would tell you when the pressure differential is too great, triggering a regen or limp mode/trouble code.

Dingo
08-15-2013, 10:35 AM
Why the F%$ don't the manufacturers just fit an injector into the exhaust downstream of the turbo to burn out the DPF . This would stop overfuelling washing bores dry of oil & wrecking engines . Would reduce wasted fuel as only one injector is "wasting fuel" .

If you want to increase exhaust gas temps , simply driev in a lower gear than normal & the increase in load will raise the temp . My van does not have all this tehcnical ****e fitted , but i do wind the revs up towards the red line every so often & i am amazed by the cloud of junk blown from the tail pipe . My previous 312 spent all its life working on the motorway ( highway)
virtually , it rarely chucked any soot out when pushed hard .

I put this down to complete combustion & high gas temps / high gas speeds clearing the pipes

flman
08-15-2013, 11:34 AM
I have heard, you can drill a 3/8" hole through the DPF core and it will run OK, and the computer will think every thing is just fine?

showkey
08-15-2013, 02:12 PM
Soot is not the only problem...........

Think there can be two or more things that can cause a DPF problem:

Soot that should be cleaned with regen when the systems works as designed and use allows full regen at a regular needed interval.

Clogging due ash and other contaminates from the oil or fuel will not removed by regen. This can happen over time usually higher mileage.

If there is another engine mechanical problem it can easily damage or plug the DPF.......especially oil consumption. Regen will not solve or replacing the DPF without correcting the root cause future disappointment.
A side note gas engines also experience catalyst damage from oil consumption, misfire, also oil ingredients in gas engine has been changed to prevent cat fouling.......from zinc etc

There has been a lot written on DPF and apply to all clean diesels.

http://www.worktruckonline.com/channel/fuel-management/article/story/2008/01/what-fleet-managers-should-know-about-diesel-particulate-filters/page/2.aspx

lindenengineering
08-15-2013, 02:33 PM
Soot is not the only problem...........

Think there can be two or more things that can cause a DPF problem:

Soot that should be cleaned with regen when the systems works as designed and use allows full regen at a regular needed interval.

Clogging due ash and other contaminates from the oil or fuel will not removed by regen. This can happen over time usually higher mileage.
There has been a lot written on DPF and apply to all clean diesels.

http://www.worktruckonline.com/channel/fuel-management/article/story/2008/01/what-fleet-managers-should-know-about-diesel-particulate-filters/page/2.aspx

I will strongly endorse the above.
Every one I have seen choked up of late has not been run on the right oil!

The big concern of course is fuel quality, a factor that is hard to overcome due to the huge variation across the US.
On a Ford factory tech course I attended recently this was a major source of discussion and debate.
Dennis

CJPJ
08-16-2013, 02:21 AM
Is there a low tech easy way to tell if the DPF is starting to plug without pulling the DPF off, is there a metric/baseline of exhaust air flow out tail pipe at idle?

Not low tech but you can read/monitor exhaust pressure differential at the DPF with a good scan tool (MB Star, Diagun, AutoEnginuity w/enhanced package). What's missing are the numbers/values that would tell you when the pressure differential is too great, triggering a regen or limp mode/trouble code.

I do recall a thread (couldn't find it with search) where the members were tracking the regeneration's : frequency , regen temperatures , elapse time.

I wish that I could tell how frequent (in miles) that the regeneration's do take place. I can:shifty:not tell, it's likely due to the good job I did insulating the van as it is relatively quiet to drive.

flman
08-16-2013, 11:35 AM
http://sprinter-source.com/forum/showthread.php?t=26121&highlight=regen

gottahavabenz
08-16-2013, 11:42 AM
I was with CJPJ, couldnt tell when it regen'd until about a month ago while waiting in my van for something and playing with my ultragauge and noticing that it in fact does have the CAT1 and CAT2 temps. I put them on the front screen and it works great. I roll down the highway averaging 500-700 degrees. When the awful moment comes when it regens it shoots up the CAT2 to around 1300 degrees, engine temp rises 10 degrees as well. It took about 20 minutes the last time I noticed for it to finish at 62MPH.

lindenengineering
08-17-2013, 05:24 AM
Guys
For info
Denver Radiator cleans particulate filters as well.
I was I there today picking up a Sprinter condenser ( a core repair)

They are happy to treat these filters for Sprinter owners
http://www.serckservices.com/
Dennis

Dieselhawk
08-19-2013, 03:44 PM
Ok,
So I got my DPF cleaned by a local shop who does oil coolers etc. The dealer put it back on and it ran fine for a day. Then half way to work this morning it coughed a couple of times, engine light came on and it shut off. I think this fault maybe different to the original as there was no loss of power like before and this time the engine light was on constantly rather than flashing. I had to get the vehicle towed to my workshop. Does anyone have a list of faults that will not allow the engine to start? I'm wondering if one of the techs who worked on it has left a sensor or harness connection loose. I'll check over it tomorrow. On the vehicles I am familiar with there are usually very few codes that will actually not allow the engine to start so if anyone has any info on this it would be much appreciated. I have the software now but it doesn't work with my comms adaptor.
Cheers

A440
08-22-2013, 04:11 AM
I have an 07 with a plugged up DPF. I guess I must be blind or something but I cannot see any flanges or clamps to remove the filter from the system. Any help much appreciated.

Thanks,
Gary

Aqua Puttana
08-22-2013, 01:28 PM
... Does anyone have a list of faults that will not allow the engine to start? ...
Cheers
Sorry for the late response.

A plugged exhaust will prevent an engine from starting.
Once had a no start Toyota that was towed in. We found it had backed into an icy snow bank and blocked the exhaust. Cleared the ice plug and everything was back to normal. How it all came together that the ice froze so tightly is beyond me. :idunno:

FWIW. vic

NBB
08-22-2013, 04:43 PM
I have ~60k miles and the DPF has gone through only 1 regen - at around 60 miles. I suspect this happened when the H44 update was done by the dealer before I bought it. My driving is simple to describe. I never accelerate hard in 1-4 gear, and the majority of my miles are on the highway with the cruise control set to 82mph. I've had zero issues of any kind with the engine.

mean_in_green
08-23-2013, 07:35 PM
Standard interval in the UK is to regenerate every 600 miles / 1,000 kms. The interval can vary but I'd be amazed if you've exceeded the normal parameters one hundred fold.

Later ECM software versions store a value for the total number of regenerations initiated, as well as initiated but not completed. My 2010 didn't have that software when built, but it does now.

showkey
08-23-2013, 09:05 PM
Standard interval in the UK is to regenerate every 600 miles / 1,000 kms. The interval can vary but I'd be amazed if you've exceeded the normal parameters one hundred fold.

Later ECM software versions store a value for the total number of regenerations initiated, as well as initiated but not completed. My 2010 didn't have that software when built, but it does now.


Many times regen can happen and the driver is totally unware.

flman
08-23-2013, 10:45 PM
Many times regen can happen and the driver is totally unware.

After you get an ultragauge you become aware, and I do not use the alarm any more, just the tone of the exhaust is my alarm.

danthewolf007
08-23-2013, 11:50 PM
There is a small catlytic converter before the dpf it may be blocked.

mean_in_green
08-24-2013, 09:07 AM
Many times regen can happen and the driver is totally unware.

Well, you wrote what I was thinking - I just wasn't sure how NBB might feel about the suggestion!

I think there's more to it though. There are owners - clearly in possession of all senses - who also haven't heard a regeneration happening. It's a distinct event in my OM651, perhaps less obvious with other engine / body types?

sailquik
08-24-2013, 01:43 PM
Hi Simon,
I'm "one of those people".
I'm very aware of what's going on with the engine in my current 2012 OEM NAFTA tune NCV3 Sprinter, just as I was in the 2010 and 2011 models I drove before this one.
To tell you the truth, I've been going to ask the technicians/service staff where I have my Sprinters serviced to pull/write down the mileage and dates when my DPF has regenerated, because I have never had any indication that the regenerations have occurred. They can see the mileage/dates with the MB SDS diagnostics for sure.
Maybe the way I drive my Sprinters (and advocate for others to drive in the same manner) keeps the DPF clean (er).
I simply do not know as there have never been any "events" where I could see or feel any "'differences". No temp spikes....no rough running or idling....no change in the smell from extra high temperature operation.
Roger

Graphite Dave
08-24-2013, 03:51 PM
I am also "one of those people". I have not heard or felt a regeneration on my 08. I do pay attention when I drive and almost never use the radio so I should hear it or feel it. I also drive using the scan gage and manually shift the transmission because it is improperly programmed (IMO) because it does not downshift on hills before reaching 99% LOD. I have adopted the "Sailquik" religion. Not to the degree as Sailquik, but I pay attention.

icarus
08-24-2013, 04:25 PM
I am also one of "those people". In 60 k, I have never noticed a regen. I have been meaning to add EGT to my ultra gauge screen but somehow never get around to it.

Icarus

sailquik
08-24-2013, 04:48 PM
Dave, Icarus, Simon:
I guess for those of us who are aware, but have never "experienced" a DPF regeneration
the old adage "If it ain't broken...don't fix it" would apply!
No?
Now that my 2012 is pretty well broken in (27 k miles), I'm getting 19-20 MPG very consistently.
I drive approx. 700 miles per week...back and forth to work @ 45-55 mph (varied terrain with a couple of pretty good hills) and then 2 6-8 hour "commutes" across MD, through the northern neck of VA, round the Hampton Roads beltways and on down to Hatteras, then back the same routes on Sunday night, so a fair mix of driving conditions.
Roger

Old Crows
08-24-2013, 04:50 PM
Ahhhh! Point of order! There are two types of regens, are there not? Passive regen occurs under certain conditions while you are driving. Active regeneration occurs when passive regen isn't effective, operating conditions don't put it into "passive" mode, or when the "system" detects that the DPF needs regeneration. The "preferred" regen is passive, I'm guessing.

Passive regen may be nearly undetectable in average driving. Active is probably always detectable by the noise, heat, stink from the exhaust while driving or when stationary.

If you are not detecting active regens... what does that tell us? 1. System isn't working; or, 2. Your operating conditions are such that you are continually passively regenerating. Sail Quick may be the case example of No. 2 as he keeps the exhaust temps high by under gearing and revving the engine higher. So absence of active regen may not be of great significance. Neither would the presence of active regens. (Except if very frequent it may be telling one to drive a bit more aggressively and keep the revs up at lower speeds.

I maybe recall only one active regen very early on. None since. But there was a time when the O2 sensor fritzed and it had to be forced to regen. Nothing since then about a year ago. Maybe 2500 miles since.

Graphite Dave
08-24-2013, 05:07 PM
Two types of regeneration would explain why some of us do not hear or feel a regeneration. If we are not deaf or inattentive, then the "Sailguik" method of driving a NCV3 must have additional benefits beyond fuel savings. I doubt that the active regeneration is beneficial to engine life. Sounds pretty brutal. Personally my next van will not be a Mercedes and will be gas powered so this discussion will be irrelevant for me. Diesels are now more complicated than a gas engine. Could be a NG or LP powered vehicle will be more economical and a much more robust design than a diesel with all the EPA required junk.

sailquik
08-24-2013, 05:27 PM
Dave,
I'm giving them another chance, but get ready for some strong constructive criticism (not of you, of course) about how the EPA requirements/regulations/tests have taken a very clean little motor (for the entire rest of this planet) and mucked it up with "stuff" that they think might make it cleaner.
CARB might be even worse.
I'll be getting the 2014 2.1 liter 4 cylinder OM-651 dual turbo (one for low speed (big one) and one for high speed (small one)) 7G-Troic 7 speed slap shift automatic transmission with 2 overdrive gears and 2 reverse gear ratios pushing the exact same 4.182:1 rear end ratio as my 2012 3.0 liter V6 (???? I think I want a 4:56:1, but it's not offered).
I will change to this newer technology, with all the bells and whistles, and see what EPA/CARB have done to this little motor with the 7 speed.
I'm especially interested since I've had a look at the gear ratios, and the 6th speed is almost the same as the current 5th gear 0.83:1 and the 7th speed is 0.7:1.
I hope to have the 2014 by the end of September. It's on the boat, needs to be reassembled in Ladson (Chicken Tariff regulations...what a complete waste of time and energy) then shipped up to the dealer in central PA.
Roger

CJPJ
08-24-2013, 05:28 PM
For one... if I could tell when regen's are taking place then I would never shut the motor off during one. I wonder if there is a slight increase in the engines Idle during a regen ,...200rpm?... A tattle tale I could watch for. Nice if MB had installed a LED for the unaware :shifty: who would like to be aware of regenerations!


:idunno:

mean_in_green
08-24-2013, 05:45 PM
Good news! The idle IS raised slightly at that time, to about 900 RPMs.

CJPJ
08-24-2013, 07:41 PM
Ahhhh! Point of order! There are two types of regens, are there not? Passive regen occurs under certain conditions while you are driving. Active regeneration occurs when passive regen isn't effective, operating conditions don't put it into "passive" mode, or when the "system" detects that the DPF needs regeneration. The "preferred" regen is passive, I'm guessing.

If you are not detecting active regens... what does that tell us? 1. System isn't working; or, 2. Your operating conditions are such that you are continually passively regenerating. Sail Quick may be the case example of No. 2 as he keeps the exhaust temps high by under gearing and revving the engine higher. . My "undecteded passive regen No. 2"... I give little concern to exhaust temps and drive with just enough throttle to cause early up shifting and low revving . . . My Sprinters service is considered hard. Doesn't get driven a hole lot ,08 with 45,000 mi. = over 12 months between oil changes ,... in 36,853mi, @ 1011:16 hrs., average speed of just 36 mph, = 19.3 mpg. , Yes my Sprinters service is considered Extreme Duty, I drive it as per one of the owner's manual Driving tips Little throttle: early upshifts... :wtf: Could call my driving manner Just enough there times I pilot my Sprinter like Humphrey Bogart piloted the African Queen , putt, putt, putt . . . , very relaxing Yet no CEL to date Knock on Wood.

bty , (Saturday night) I think I'll use the Sprinter to pick up a Extra Large Pizza! you know Extreme Duty!

:smilewink:http://www.youtube.com/watch?v=YNNH47eMx1g

showkey
08-24-2013, 10:04 PM
I too am one of those that does not notice regen.......thats why I brought it up........

The only thing I do notice now after many miles ........during regen with the scan gauge is MAP value is limited to 30-30 if not in regen 35-37 can be seen.........so if I am climbing I do notice reduced power for about 10 minutes.

With a class C I have not heard, felt or smelled anything out of the norm during regen.

As for active and passive..........I thought passive was what we are doing will driving and active is what the dealer does with the MB tester to force regen in the repair stall????????

NBB
08-25-2013, 02:48 AM
My observation is straight from an OTC Genisys tool. There are parameters for grams (or whatever units) of particulate in the DPF. Not sure how it gets that number, but it is there. There is another parameter storing the miles at last regen. This was confirmed just a few weeks ago by the dealer when I had my EGR inspected. It was clean. DPF regens are triggered by grams of particulate, not miles or months.

CJPJ
08-25-2013, 04:13 AM
To point out regenerations ...is it plausible that a thermocouple attached to the DPF could light a LED?

...:thinking:

gottahavabenz
08-25-2013, 11:48 AM
Or just an Ultragauge, inexpensive, useful.

VanDiesel
09-12-2013, 02:37 PM
As to CJPJ 's idea "To point out regenerations ...is it plausible that a thermocouple attached to the DPF could light a LED?" -
Certainly seems plausible. Here's another LOW tech idea - Purchase a CHEAP remote indoor/outdoor thermometer ( About $15 - $20 max) Locate the outdoor sensor INSIDE the van on the floor (above the DPF) ,place display unit on dash. I can't believe that a 1300 degree regen temperature at the DPF wouldn't show at least some noticeable increase on the sensor inside the van regardless of how much shielding and insulation is between the two.

Of course, you can remove both modules from the van easily and use for their "intended" purpose at any time.

suzieque
09-12-2013, 04:32 PM
Most cheap indoor / outdoor thermometer will burn up at 200 degree Fahrenheit.

jackpinner
09-12-2013, 06:48 PM
I own 2 2007, do these units have a regen. I drive one but it's almost all hi way driving & the other my employee drives.

CJPJ
09-12-2013, 09:51 PM
I own 2 2007, do these units have a regen. Yes. 2007 is the first year to have a DPF, and all DPF's need periodic regenerations. you are to "remove it @ 100,000mi. and inspect it for plugging and replaced if needed , if it doesn't need to be replace at that time then start removing and inspecting every 10,000mi. until it is replaced with a new one".

VanDiesel
09-12-2013, 11:40 PM
Suzique -Agreed temp sensor will not survive 200+ degrees. Hence, the keyword "inside" . If the inside van floor rises over 200 degrees you will know without a sensor.

Bobnoxious
04-30-2016, 09:55 PM
BBlessing,
My experience with NCV3's with DPF (granted they were 2010 or later Mercedes Benz, not Dodge or Freightliner) is pretty much the opposite.
Keep some revs on them >2400 for sure, and a few times per day "blow them out" with heavy acceleration to get the temps up and revs over 3000.
Works for me!
Roger

Sailqik's advise is 100% Bobnoxious Approved! Not going going to hurt them a bit.

Bobnoxious
05-07-2016, 05:38 PM
I don't know who bill is. anyhow, what I was getting at, is that putting your foot in it at low rpms is what is plugging up the dpf. yes high rpm driving is good for clearing out things, but it is good or better to get there gently.

bruce blessing


IMHO Considering she red lines at 4000 RPMS, "Gently" would be anywhere from 2000-3200 rpm's

Bobnoxious
05-07-2016, 06:04 PM
BBlessing,
My experience with NCV3's with DPF (granted they were 2010 or later Mercedes Benz, not Dodge or Freightliner) is pretty much the opposite.
Keep some revs on them >2400 for sure, and a few times per day "blow them out" with heavy acceleration to get the temps up and revs over 3000.
Works for me!
Roger

Not that he needs my "Seal of Approval" but I agree completely with Roger. The brief time I had my Ultra Gauge Blue functioning. I noticed one exhaust temp, I am guessing the first sensor behind the turbo?, measuring around 600-700 degrees running at about 2400 rpm's. The sweet spot of throttle position relative to RPM's while accelerating is important also.

SprinterHelp
04-10-2017, 05:22 AM
QUESTION, what if you took out DPF and poured a cup of diesel into the DPF. Seems like a cup is enough to pour into filter and seep into all holes before disappearing. Then run the vehicle. Seems same theory as raw diesel being fed into dpf via ECU during regen process? anyone try this?