He said nothing to disagree with. He is giving a description of the system. I think we all can agree on the components of the system and each components purpose. What I attempted and failed at discussing was what problems occur when the ceramic particulate filters start to get clogged and the exhaust volume is reduced as an effect of system failure. No, def Has no direct involvement with the carbon in the exhaust but it does have a great deal to do with it indirectly. That’s the point you guys are missing. It’s easy for everyone to claim they’re all master techs And the worlds leading authority on diesel engines here online. I’ve had six trucks with a def system, from the very first generation through the most current. I’ve had countless hours of service at multiple dealerships all over the eastern half of the United States Relating to the def and emissions system. The company I’ve worked for for the past 25 years has over 250 trucks who does all of the Non warranty Service. I’ve spoken to the shop foreman who’s been there for over 40 years numerous times about this subject. I’ve spoken to dozens of Master Tech’s at Peterbilt at numerous dealerships over the past decade. I’ve also read the service bulletins from the engineers at both Detroit and Cummings about this issue. However, none of those guys have any idea what they’re doing and you guys are all geniuses on the subject of carbon buildup and what causes it. This has became a ridiculous conversation, all based on a hopefully helpful comment about some peoples misunderstanding that Def issues are industrywide by all manufactures and not just an issue with Mercedes-Benz sprinter engines.Sadly, it has became impossible to avoid online “know-it-all’s” that spend their time correcting everybody on issues that they think they know a great deal more than they really do. You guys have a nice day.
Continuous DEF Problems with Sprinters
- Thread starter RatDog
- Start date
So as I understand the squires of the wrench (p1>) say the egr impacts the dpf, def,scr systems. Pondering this I can see it. As it leads in the chain of dysfunction.
In my sprinter as time passed I cleaned the egr more frequently sometimes @ 35-40k intervals.
I can see where this was beneficial in hindsight.
When it was pointed out (the soot manifold) on the pass side of engine i was dismayed. Yet went to Lucas for the "deep clean" product in an attempt to thwart that manifold from plugging up (which it did once).
While I have gained here I am disappointed that customers are fed a load of bull.
I ask ?'s of mechanic's to understand also (to alleviate reoccurrence). This reinforces the perception that you can't trust anyone in what they say.
Once again I am ashamed of my species.
In my sprinter as time passed I cleaned the egr more frequently sometimes @ 35-40k intervals.
I can see where this was beneficial in hindsight.
When it was pointed out (the soot manifold) on the pass side of engine i was dismayed. Yet went to Lucas for the "deep clean" product in an attempt to thwart that manifold from plugging up (which it did once).
While I have gained here I am disappointed that customers are fed a load of bull.
I ask ?'s of mechanic's to understand also (to alleviate reoccurrence). This reinforces the perception that you can't trust anyone in what they say.
Once again I am ashamed of my species.
Well...I thought I was being nice....anyways...here goes.
The only "DEF heating process" is the small heater in the DEF tank that thaws frozen fluid...that's it.
The "excess carbon"...I'm assuming you mean particulates or soot...that normally builds up in the DPF is burned off in the regeneration process...either "passive" just from the heat of the exhaust alone or "active" which is when the engine injects extra fuel into the exhaust stream to make the required heat for regeneration to occur.
If the DPF cannot clean itself with regeneration, exhaust backpressure goes up and will trigger at least one or more fault codes...likely immediately as backpressure is one of the things measured by the ECM to determine when to start and end a regeneration event. So driving around with one that contains "excess carbon" is operator error...not system failure.
DPF restrictions (even after a regen) can also be caused by other operator errors. The wrong or excessive amounts of motor oil, goofy home brew fuel additives, using something other than ULSD for fuel etc. Again...the system will likely trigger a fault code not to be ignored.
I didn't go "look up a diagram" etc...I tried to educate you on your errors in your post. I know how these systems work...perhaps you should look at a diagram and look at what order these systems are in. Then you will see that the DEF part of the system is after the DPF part of the system so its "heating process" (whatever that is) doesn't affect it. In all your discussions and research...tell me how the DEF part of the system affects the DPF soot loads?
And.....based on the attitude in your responses here...You are exactly the type of customer/driver I would say whatever I needed to just to make you go away.
I'm done...I have trucks to fix.
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If that is your attitude when you walk into a shop...you will get the go away type of answers too likely.
The guy on the shop floor at the dealer (or Engine dealer) has likely had dozens of hours of training each year for the past 10 years or so..just on emissions crap.
He also (unfortunately) if the vehicle is under warranty is having to follow the instructions of someone in an office cubicle many miles away at the OEM who has to "authorize" most of the repairs and only allow certain things. He also likely has to listen to his shop foreman who may not have had the training. He also has to try and extract good information from the driver and weed out the stuff that doesn't matter.
These systems are not the greatest....but the "parts swappers" aren't the big issue.
FV
I formally request that my account " blind squid" be removed & or eliminated from this sandbox.
(Eliminated from the entire site)
If this request is insufficient to make this happen than feel free to state what must be done to effect such action.
I formally request that my account " blind squid" be removed & or eliminated from this sandbox.
(Eliminated from the entire site)
If this request is insufficient to make this happen than feel free to state what must be done to effect such action.
You're only hurting yourself by requesting this.
I refuse to do this.
Edit: this is why I work on trucks, and not with people. I never want to be a service manager. Service managers have the worst job in the world. They're often not as deep into the technical side of things, especially considering all of the nuanced ways that trucks fail and why, so they're forced to supply a narrative instead.
I'm reminded of some poor Russian guys that had a turbo blow on the highway and the dpf got saturated with engine oil. They needed a turbo and a DPF. The thing is, the dpf was 5 days old, just replaced because their injectors were also bad. They had just spent 4k, now they needed another 4k dpf and a 2.5k turbo plus four hours of labor, and they needed to spend another 3k in just parts on injectors alone or risk yet another $4k dpf. Understandably, they were pissed. Who's lap did this fall into? The service manager's. Did this customer get fed a line to stop them from screaming in the lobby? You betcha.
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Anyone interested in this topic can simply google carbon build up in desel def. apparently all these master genius ultra super techs are completely unaware of the common problem of the particulate filters only lasting less than half there expected lifespan before having to be cooked off because of blockage on the face.
"he common problem of the particulate filters only lasting less than half there expected lifespan before having to be cooked off because of blockage on the face."
Well aware of that...still has nothing to do with DEF...the system that is AFTER the particulate filter
I "Googled it" and the first 2 pages were all about carbon/soot issues from EGR, bad fuel, bad oil and other things ...NO DEF mentioned as a cause at all.
Google carbon build up DPF....lots of relevant info.
You said the DEF indirectly affects the DPF and causes it to plug up...tell me how then?
Well aware of that...still has nothing to do with DEF...the system that is AFTER the particulate filter
I "Googled it" and the first 2 pages were all about carbon/soot issues from EGR, bad fuel, bad oil and other things ...NO DEF mentioned as a cause at all.
Google carbon build up DPF....lots of relevant info.
You said the DEF indirectly affects the DPF and causes it to plug up...tell me how then?
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Oh, you want to argue the proper use of terminology. I would have thought that you were aware that it is common place, slang if you will to refer to the entire system as the DEF system. Since is’s the DEF fluid after it’s mixed with the catalyst to release the ammonia that captures the particulates that are trapped in the filter. One could argue that it’s the same system. That’s really a silly conversation and entirely off topic. I noticed you never really address the topic. By the way, I thought you said you were done?
That statement right there proves you don't understand how an emission system works or whoever you are talking to doesn't or you aren't understanding what they are telling you.
Between 2008 and 2010, trucks were required to have DPFs to remove particulates, but NOx levels could be controlled by EGR. DEF/SCR was not required.
By 2011, emission mandates demanded even lower levels of NOx, so most manufacturers added DEF/SCR to further lower NOx emissions. The notable exception was International and their Maxxforce engines (which didn't work as intended).
DPFs remove particulates, and are cleaned by regeneration, either by heating by post injection and oxidation catalysts, or with burner systems. Particulate -free exhaust gases then have DEF sprayed into them, releasing ammonia, then NOx reduction reactions take place in the SCR.
On occasion, a DPF meltdown will damage the Scr, causing Scr catalyst efficiency problems. Def/scr cannot affect DPFs because DPFs are located upstream.
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DOC or DPF face plugging has many possible causes, like excess engine oil from the turbo, crankcase ventilation system, base engine wear, and excess soot from boost leaks, worn/damaged turbos, degraded injectors, clogged air filters, previous DOC damage, etc.
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with some systems that is true and with some, not. You guys just want to argue these irrelevant off topic points in an attempt to showcase what you know or may think you know. We’re so far off topic now it’s rather pointless. But, I guess I should’ve known this. These pointless childish arguments are really all that can be found online anymore. It’s just people Starved for attention.
Please explain in depth what it is you're talking about so we can all understand. From here, it looks like you are showcasing your ignorance, and you have a golden opportunity to prove us wrong.
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Be happy to and I’ll type slowly for your benefit. The mission systems problems including the entire DEF system are not specific to the sprinter van. These emission issues are happening industrywide with other diesel engines. Some people were under the impression that these issues were only happening with their sprinter vans and nothing else. I learned a long time ago the best thing to do regarding truckstops is to just go in do what you need to do and leave. Talking to other drivers was just a waste of time. Everybody’s an expert on everything. everybody is an expert mechanic. They will argue about the time of day just to hear the sound of their own voice. But I’ll take the responsibility for this ridiculous conversation. I should’ve known better. This apparently is the online version of a truck stop.
Of course after treatment problems plague all manufacturers. This is common knowledge.
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I sold my Diesel str-8 truck in 2007 and have had a Gas van of some type since ...
This topic is about DEF ..
My thoughts ..
another day .. another bowl of Popcorn
This topic is about DEF ..
My thoughts ..
another day .. another bowl of Popcorn
So it's your fault then.All I know is, twice I have purchased a new diesel-powered van. Following each purchase, there was an immediate and unrelenting increase in the price of diesel fuel.
Stay safe,
KG
I have gas but notice that Diesel is over $3 again
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