Frequent regens (~100 miles); no help from the dealer

[resoverlord]

I purchased a used 2020 3500 HO SRW in January. I used to own a 2019 tradesman, and basically traded up to a Laramie. I never used to watch the DPF gauge or regeneration on the old truck because it almost never happened (every 24 hours, and the gauge would never come up). As such, I pretty much ignored it on the new truck as well.

In late February, I got a check engine light; p2459, DPF regeneration frequency too high. I bought it to the dealer right away.

They ran a manual regeneration, said "it's good to go", and send me on my way. On the way out of the dealer the DPF gauge started coming up right away; it was almost fully blocked again by the time I turned around and brought it back. They took the truck again, and (after another 5 day wait), said they performed another regeneration, drove it 30 miles, and it's good to go.

Once again, as soon as I left the dealer the gauge started coming back up again. I brought it back, and was basically told if there is no check engine light, there's nothing they can do and there's nothing wrong with the truck. I told them I had a check engine light (DPF regeneration to frequent), and the problem still exists. I'm sure after a certain number of regenerations the check engine light will come back on, but now I'm stuck driving around having a regeneration every 100 miles until the light comes on.

I'm very frustrated by all this; the fuel mileage obviously suffers, I hate having the truck run high-temperature all the time, and the whole mentality of "no check engine light, it's not broken" is very frustrating.

Any ideas?

Here is my regeneration log, if you're interested:

59,816 (by the dealer the first time)
59,864 (by the dealer the second time)
60,002 -> 60,028
60,116 -> 60,133
60,214 -> 60,249
60,350 -> 60,371

 

[resoverlord]

This is what they say they checked

 

[resoverlord]

@RamCares Is this the kind of thing you can help with?

 

[resoverlord]

I ended up connecting with RamCares chat. Truck has to be at a dealer for them to open a case. Dealer doesn't want the truck if it doesn't have a CEL. I'm spinning wheels...

 

[jabartram]

I have a neighbor bought a 21 Diesel waited 9 months for it, drove it a couple months and started getting that same code, dealership installed a new "catalytic converter" waited for the part for a month.. they also replace a trans temp sensor.

 

[resoverlord]

I have a neighbor bought a 21 Diesel waited 9 months for it, drove it a couple months and started getting that same code, dealership installed a new "catalytic converter" waited for the part for a month.. they also replace a trans temp sensor.

I'm assuming they meant the DPF filter (since the cummins doesn't have a catalytic converter). Wonder if I have a bad one.

 

[superjoe83]

I'm assuming they meant the DPF filter (since the cummins doesn't have a catalytic converter). Wonder if I have a bad one.

They have two catalysts in the exhaust system the first one is the DOC, (diesel oxidation catalyst) which is part of the DPF assembly, the second is in the SCR assembly.

 

[resoverlord]

They have two catalysts in the exhaust system the first one is the DOC, (diesel oxidation catalyst) which is part of the DPF assembly, the second is in the SCR assembly.

Got it. If a DPF were to clog, is it typically the catalyst or the filter itself?

 

[superjoe83]

Got it. If a DPF were to clog, is it typically the catalyst or the filter itself?

Most likely the filter itself, the DOC can "face plug" but that usually only happens with extended idling or low load conditions where the exhaust system never gets up to temp.
It sounds like you have an issue upstream that is causing excessive soot, or the DOC is not functioning properly during a regen and not creating the heat needed to oxidize the soot in the DPF. The only way to diag the DOC would be to start a forced regen and watch all of the exhaust system temps with a scan tool.

 

[resoverlord]

Most likely the filter itself, the DOC can "face plug" but that usually only happens with extended idling or low load conditions where the exhaust system never gets up to temp.
It sounds like you have an issue upstream that is causing excessive soot, or the DOC is not functioning properly during a regen and not creating the heat needed to oxidize the soot in the DPF. The only way to diag the DOC would be to start a forced regen and watch all of the exhaust system temps with a scan tool.

I have an Alpha OBD unit and I have the option to force a regeneration. What temperature should I watch during the process (which gauge), and what should it raise to?

Thanks for your help.

 

[superjoe83]

I have an Alpha OBD unit and I have the option to force a regeneration. What temperature should I watch during the process (which gauge), and what should it raise to?

Thanks for your help.

Which obd adapter are you using with alfa?

 

[resoverlord]

Which obd adapter are you using with alfa?

ODBLinkMX+

 

[Will_T]

I have an Alpha OBD unit and I have the option to force a regeneration. What temperature should I watch during the process (which gauge), and what should it raise to?

Thanks for your help.

On mine I monitor EGT1 and 3. EGT3 spikes during a regen.

 

[superjoe83]

ODBLinkMX+

Good, this should be easy, I would monitor temps and regen status on my '18 and used the obdlink app over alfa because I felt it was easier to use for that purpose. With that said you will need to set up the obdlink app to monitor temps, I found that alfa didn't display all of the exhaust temp readings for some reason, so using obdlink was nessasary, once you start the regen with alfa you can exit the app, the truck will finish the regen without alfa hooked up to it. Once the regen is started you will go into obdlink and monitor the temps and whatever else you want to look at.
I have attached a screen shot of my obdlink PID list, you are mostly interested in the first three exhaust temp readings, #1 is before the DOC, this will get to around 6-700 degrees during the regen. #2 is after the DOC, once the regen has started and once the #1 temp gets over 500 degrees you will start to see this temp climbing since the ecm is preforming a very late injection event which essentially injects fuel on the exhaust stroke which sends the unburnt fuel to the DOC which oxidizes it causing the heat for the DPF cleaning, the DOC outlet temp should quickly start rising up to just over 1000 degrees, the third sensor is after the DPF and this will rise up to around 9-1000 degrees also, if all of this seems to be working properly then the DOC is likely in good shape. I would start to suspect an upstream problem (injectors, egr, turbo/air intake restriction problem)
Let me know if you need help setting up obdlink, or have any questions

 

[resoverlord]

Good, this should be easy, I would monitor temps and regen status on my '18 and used the obdlink app over alfa because I felt it was easier to use for that purpose. With that said you will need to set up the obdlink app to monitor temps, I found that alfa didn't display all of the exhaust temp readings for some reason, so using obdlink was nessasary, once you start the regen with alfa you can exit the app, the truck will finish the regen without alfa hooked up to it. Once the regen is started you will go into obdlink and monitor the temps and whatever else you want to look at.
I have attached a screen shot of my obdlink PID list, you are mostly interested in the first three exhaust temp readings, #1 is before the DOC, this will get to around 6-700 degrees during the regen. #2 is after the DOC, once the regen has started and once the #1 temp gets over 500 degrees you will start to see this temp climbing since the ecm is preforming a very late injection event which essentially injects fuel on the exhaust stroke which sends the unburnt fuel to the DOC which oxidizes it causing the heat for the DPF cleaning, the DOC outlet temp should quickly start rising up to just over 1000 degrees, the third sensor is after the DPF and this will rise up to around 9-1000 degrees also, if all of this seems to be working properly then the DOC is likely in good shape. I would start to suspect an upstream problem (injectors, egr, turbo/air intake restriction problem)
Let me know if you need help setting up obdlink, or have any questions View attachment 34322

Awesome, I’ll give it a shot!

 

[RamCares]

I ended up connecting with RamCares chat. Truck has to be at a dealer for them to open a case. Dealer doesn't want the truck if it doesn't have a CEL. I'm spinning wheels...

Hi,
We are happy to hear you have a case made for this concern. Your case manager is in the best position to help. If you would like to document your case, get an update, or speak to your case manager, feel free to reach out to us via PM.

Rob
Ram Cares

 

[Jsboening]

I swear Ram chat is run by Jen Psaki.

 

[mguebert]

ROTFLMAO

 

[rsday75]

I'm interested in this as well. My 2019 got that code. Before the code, I got a regen every 24 hours or 2-3 tanks of fuel depending on driving style, towing, etc.
Took my truck to the dealer and they "updated the PCM" and sent me on my way.
I have had the truck back to the dealer twice since them as I can't get more than a couple hundred miles between regens......that is all highway driving......3 times per tank on an all interstate trip....
It hovers right around 100 miles per regen in mixed driving. Cold morning idle and a couple of shorter trips had a regen in 60 miles......
I was told by the dealer no CEL, then nothing is wrong......but something is defiantly wrong with a regen every 100 miles. The no CEL nothing is wrong mindset of "mechanics" is some ********. I say mechanics in quotes as most are nothing but parts replacers based on what a code reader says. Few can properly diagnose a issue today.......
I have needed my truck, so I have been living with it for the past few months, but I guess it will go back to the dealer AGAIN when I can live without it for another week........

It is a shame it comes to the customer having to open a case with Ram to get a dealer to really look into an issue.......

 

[resoverlord]

It's been at the dealer about 10 days now (they asked me to bring it in, so I paused on doing anything else myself with it). No updates as of yet.