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Automatic Regen too often

In the monster paragraph above is as you pointed out the diff pressure info:

The PCM determines the load condition of the DPF based upon the exhaust gas pressure upstream and downstream of the DOC/DPF. A pressure differential sensor provides the pressure input to the PCM.
After regeneration, the PCM reads the actual pressure difference at the DOC/DPF and compares it with a reference value. From this comparison, the PCM determines the ash quantity inside the DOC/DPF

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I'd love to know what that reference value is so I could see it on the PID display.
 
I also find the stationary de-soot interesting:

11 - Exhaust System / FILTER, Diesel Particulate / Standard Procedure

STANDARD PROCEDURE - STATIONARY DESOOT

WARNING:
Due to the fact that the vehicle may be left unattended for up to one hundred (100) minutes during this procedure, every precautionary measure must be taken to ensure that the vehicle cannot be stolen and that no person comes in contact with the hot exhaust or hotexhaust gases during the procedure.​

NOTE:
When using Diagnostic Scan Tool software at release 9.05, the fuel minimum specification to run the test is 1/4 of a tank of fuel.​

1. Fill the vehicle with three (3) gallons of Ultra Low Sulfur diesel fuel to perform the procedure.

NOTE:
In order for Stationary De-Soot to begin, the vehicle must be parked with the parking brake engaged, be at normal operating temperature, have no active DTC’s unrelated to De-Soot, and have at least three gallons of fuel. If any of these conditions are violated after Stationary De-Soot begins, or if the service brake or accelerator pedal is pressed, Stationary De-Soot will abort.​

2. Position the vehicle on a NONFLAMMABLE surface such as concrete.

WARNING:
Exhaust temperatures will be extremely high. Do not perform this procedure on flammable surfaces such as asphalt, grass, etc. or adjacent to property that may be damaged by the exhaust gases, or in a location where individuals may be required to pass adjacent to the exhaust.​

3. Apply the parking brake.
4. Position the shift lever in Park or Neutral.
5. Lower the spare tire down as far as possible. It is not necessary to remove the spare tire from the vehicle.
6. Mark an area 12 feet (3.66 meters) by 12 feet (3.66 meters) surrounding the exhaust outlet. The exhaust outlet should be six feet from the fore and aft ends of the marked off area.

NOTE:
Ensure that the “HOT EXHAUST” labels are facing outward.​

7. Ensure that the hood remains closed during the stationary regeneration operation.
8. If not already performed, connect the Diagnostic Scan Tool to the vehicle.
9. Start the engine.
10. Power ON the Diagnostic Scan Tool.
11. Scroll to the Powertrain Control Module (PCM) menu
12. Select Stationary De-Soot

NOTE:
During Stationary De-Soot, engine RPM will be elevated to 1,100 RPM. When the engine RPM returns to normal idle, the Stationary De-Soot has completed or aborted.​

13. Initiate Stationary De-Soot.

NOTE:
Stationary De-Soot may take up to one hundred (100) minutes to complete. It is not necessary to monitor the stationary regeneration cycle the entire one hundred minutes. Periodic monitoring of the cycle can be accomplished by monitoring the percent of completion through the EVIC or by reviewing the percent of completion on the scan tool.​

14. Stationary De-Soot will automatically abort once the cycle is complete. If Stationary De-Soot needs to be aborted prior to the end of the cycle, any of the following manual methods can be used:
  • Turning the ignition OFF
  • Depressing the brake pedal
  • Moving the PRNDL from P/N to D/R
15. Once Stationary De-Soot is complete, remove the antitheft device.
16. Position the spare tire back into its stowage position.
17. Once the regeneration is complete, the vehicle needs to be driven above 86 km/h (55 mph) for 15 minutes to allow the DPF differential pressure sensor to get a clear reading.

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Lower the spare tire?? Man that must get REALLY hot!
 
11 - Exhaust System / FILTER, Diesel Particulate / Diagnosis and Testing

DIAGNOSIS AND TESTING - DIESEL PARTICULATE FILTER

EVIC Message Center - Message - Catalyst Full
The Powertrain Control Module (PCM) monitors the soot load in the diesel particulate filter. Under normal operating conditions the diesel particulate filter is self-cleaning, where accumulated soot is converted to ash. Under light load operating conditions, the driver may be notified via the vehicle's Electronic Vehicle Information Center (EVIC) message center "CATALYST FULL: SEE OWNERS MAN" will be displayed on the overhead console of your vehicle if the exhaust particulate filter reaches 80% of its maximum storage capacity. Under conditions of exclusive short duration and low speed driving cycles, your 6.7L diesel engine and exhaust aftertreatment system may never reach the conditions required to remove the trapped PM. If this occurs, “Catalyst Full See Owner Manual” will be displayed on the overhead console in your vehicle. If this message is displayed you will hear one chime to assist in alerting you of this condition. Catalyst Stat::::::::::80% Catalyst Stat::::::::::80% will replace the message “Catalyst Full See Owner Manual” after it is displayed for one minute. The PCM will continue to monitor the amount of particulate matter trapped in the particulate filter. This message indicates the percentage of the particulate filter capacity that has been used. By simply driving your vehicle at highway speeds for as little as 45 minutes you can remedy the condition in the particulate filter system and allow your diesel engine and exhaust aftertreatment system to remove the trapped PM and restore the system to normal operating condition. Catalyst Stat:::::::::::80%, 90%, 99%Catalyst Stat:::::::::::80%, 90%, 99% If you are unable to drive your vehicle under these conditions for an extended period of time after the initial warning notification, the PCM will continue to monitor the particulate filter and will display the progression of particulate filter usage (80, 90, 99%) on the EVIC message center. CATALYST FULL SERVICE REQD If the particulate filter reaches 99% of its capacity, the overhead console in your vehicle will chime twice and display the message CATALYST FULL SERVICE REQD. At this point the PCM will register a fault code, the instrument panel will display a MIL light and the PCM will de-rate the truck, reducing its horsepower and torque output. The PCM de-rates the engine in order to limit the likelihood of permanent damage to the aftertreatment system. If this condition is not corrected and a dealer service is not performed, extensive exhaust aftertreatment damage can occur. In order to correct this condition it will be necessary to have the truck serviced by your local authorized dealer.

Intervention Regeneration Strategy – EVIC Message Process Flow (Late Build) The 6.7L diesel engine meets all EPA Heavy Duty Diesel Engine Emissions Standards, resulting in the lowest emitting diesel engine ever produced. NOTE: Depending on the build date of your vehicle or if the software has been updated, therevid may display the following messages. To achieve these emissions standards, your vehicle is equipped with a state-of-the-art engine and exhaust system. The engine and exhaust aftertreatment system work together to achieve the EPA Heavy Duty Diesel Engine Emissions Standards. These systems are seamlessly integrated into your vehicle and managed by the PCM. The PCM manages engine combustion to allow the exhaust system’s catalyst to trap and burn Particulate Matter (PM) pollutants, with no input or interaction on your part. Additionally, the overhead console in your vehicle has the ability to alert you to additional maintenance required on your truck or engine. Refer to the following messages that may be displayed on your Electronic Vehicle Information Center (EVIC):

Exhaust System — Regeneration Required Now “Exhaust System—Regeneration Required Now” will be displayed on the overhead console of your vehicle if the exhaust particulate filter reaches 80% of its maximum storage capacity. Under conditions of exclusive short duration and low speed driving cycles, your 6.7L diesel engine and exhaust aftertreatment system may never reach the conditions required to remove the trapped PM. If this occurs, “Exhaust System — Regeneration Required Now” will be displayed on the overhead console in your vehicle. If this message is displayed, you will hear one chime to assist in alerting you of this condition. By simply driving your vehicle at highway speeds for as little as 45 minutes, you can remedy the condition in the particulate filter system and allow your6.7L diesel engine and exhaust aftertreatment system to remove the trapped PM and restore the system to normal operating condition. Exhaust Filter XX% Full Indicates that the Diesel Particulate Filter (DPF) is approaching full. Exhaust System — Regeneration in Process Indicates that the Diesel Particulate Filter (DPF) is self-cleaning. Maintain your current driving condition until regeneration is completed. Exhaust System — Regeneration Completed Indicates that the Diesel Particulate Filter (DPF) self-cleaning is completed. If this message is displayed, you will hear one chime to assist in alerting you of this condition. Service Required— See Dealer Now Regeneration has been disabled due to a system malfunction. At this point the engine PCM will register a fault code, the instrument panel will display a MIL light. IMMEDIATE SERVICE IS REQUIRED. See your authorized dealer as damage to the exhaust system could occur soon with continued operation. Exhaust Filter Full — Power Reduced See Dealer The PCM de-rates the engine in order to limit the likelihood of permanent damage to the aftertreatment system. If this condition is not corrected and a dealer service is not performed, extensive exhaust aftertreatment damage can occur. In order to correct this condition it will be necessary to have your vehicle serviced by your local authorized dealer. IMMEDIATE SERVICE IS REQUIRED. See your authorized dealer, as damage to the exhaust system could occur soon with continued operation.
 
Forgive the rudimentary sketches and the silliness but this is the best way I could describe / visualize what I’m explaining. And why I think these trucks have issues.

If we think of active regeneration as the finish line to a race;

This is how the “race” is currently set up:IMG_7081.jpeg

This is how it should be:IMG_7082.jpeg

The way it exists now just leads to regeneration happening more often than it should as far as I can tell. Unless I’m mistaken or missing something?
 
11 - Exhaust System / SENSOR, Differential Pressure / Description

DESCRIPTION

The Differential Pressure Sensor (DPS) (2) is remotely mounted on the Diesel Oxidation Catalyst/Diesel Particulate Filter (DOC/DPF). Two pressure hoses (6) measure pressure before and after the DOC/DPF. The sensor is critical for fail-safe of regeneration strategy, because it interprets high pressure drops as possible high soot loads.

Diff Pressure Sensor.JPG
 
Here are the PIDs I monitor now religiously:

(Some of the PID names are cut off, when my CTS3 gets back from RMA repair, I'll post the correct names):

PF_REGEN_AVGT = Minutes since last Regen. This lets me track the 24 hour regen cycle and if the truck is "happy". This value should be close to 1440 minutes (24 hours) if passive regen has been working and we are only getting the timed reged.
PF_REGEN_AVGD= Distance since last Regen

PF_REGEN_P = Percentage before next Regen (100% = Regen about to happen). I set mine with a warning at 90%.
DPF STAT = Switches to ON when a Regen is in progress (again I set a warning but I can't yet get it to work properly)
DPF Press = This should be the key value determining soot load.

EGT1
EGT2
EGT4

Batt - Always monitor my battery so I know when Alternator or Batts are not behaving.

Here is the EGT diagram:

01a-Emissions System-2020 Ram 3500.png

Here is an example of a "I'm happy screen" during a timed regen, nice high PF_REGEN_AVGT:

IMG_1063.jpg

Here is an active regen (But not happy). Took pic before temps got up though:

IMG_1430.jpg
 
Thorvald said:
Here is the DPF section from the manual:

11 - Exhaust System / FILTER, Diesel Particulate / Description

DESCRIPTION
  • The first component of the Aftertreatment System consists of two catalyst elements, working together to drastically reduce tailpipe emissions:

DIESEL OXIDATION CATALYST (DOC)
  • The Diesel Oxidation Catalyst (DOC) is a ceramic flow through substrate coated with a catalyst washcoat that is integral to the DOC and resides in the fronthalf of the assembly. The DOC treats engine exhaust gases by converting harmful carbon monoxide, unburned hydrocarbons and other compounds intowater, carbon dioxide and heat.

DIESEL PARTICULATE FILTER
  • The Diesel Particulate Filter (DPF) is a wall-pass ceramic filter substrate coated with a catalyst washcoat. It is located just downstream of the DOC. Exhaustgases flow from the DOC into the catalyzed diesel particulate filter (DPF) which traps and accumulates particulate matter, and further treats the exhaustgases to reduce any remaining unburned hydrocarbons and other harmful compounds. The trapped particulate matter will be periodically removed from theDPF via a regeneration process controlled by the engine’s Powertrain Control Module (PCM).

OPERATION
  • The oxidation catalyst raises the exhaust gas temperatures to regenerate the DPF, which is passive regeneration. If the passive regeneration cannot keep upwith the build up of soot in the DPF, the Powertrain Control Module (PCM) will actively regenerate the DPF to burn off the soot. Residue remains inside theDPF in the form of non burnable ash. Ash comes from the oils and other materials that are trapped in the oils and are present in the soot. The catalystcontains a large number of parallel channels, which run in the axial direction and are separated by thin porous walls. The channels are alternatively open atone end, but plugged at the other. The exhaust gases flow through the walls and escape through the pores in the wall material. Particulates, however, aretoo large to escape and are trapped in the monolith walls. The PCM starts the regeneration of the DPF if the soot load exceeds a performance map value.The PCM determines the load condition of the DPF based upon the exhaust gas pressure upstream and downstream of the DOC/DPF. A pressure differentialsensor provides the pressure input to the PCM. During the regeneration process, the PCM raises the temperature in the DOC/DPF to burn off the sootaccumulated. Under normal operation, the engine does not produce enough heat to oxidize the soot inside the DOC/DPF. This process requirestemperatures above 550 ºC (1,022 ºF). After regeneration, the PCM reads the actual pressure difference at the DOC/DPF and compares it with a referencevalue. From this comparison, the PCM determines the ash quantity inside the DOC/DPF.
Click to expand...
When the dealership replaced my DPF the tech and I looked down the hole of the old one and the screen appeared to be clear, with some evidence of heat damage. I was getting regens every 2 engine hours/100 miles and we were both expecting to see evidence of soot loading. None appeared to be present, at least where we could see. And I have never had any evidence of sooting in my tailpipe.
 
CaptainMike said:
When the dealership replaced my DPF the tech and I looked down the hole of the old one and the screen appeared to be clear, with some evidence of heat damage. I was getting regens every 2 engine hours/100 miles and we were both expecting to see evidence of soot loading. None appeared to be present, at least where we could see. And I have never had any evidence of sooting in my tailpipe.
Click to expand...
Unless there’s a hole in the DPF you shouldn’t see soot at the tailpipe. The only way soot appears there is if the DPF media or the pressure vessel fails in some manner and allows soot to bypass. (Which should be detected by the PM sensor at the back of the SCR and set off a DTC)

It would have been interesting to see pictures of that heat damage. That too is a rarity but something that should have DTC’s associated with it.
 
CaptainMike said:
When the dealership replaced my DPF the tech and I looked down the hole of the old one and the screen appeared to be clear, with some evidence of heat damage. I was getting regens every 2 engine hours/100 miles and we were both expecting to see evidence of soot loading. None appeared to be present, at least where we could see. And I have never had any evidence of sooting in my tailpipe.
Click to expand...
I am in the middle of a similar issue but it was 20-50 miles, some (most) days it was happening multiple times a day. All highway. They've bore scoped it a few times with a camera. Pre maf sensor change it appeared clean, but afterwards they did another bore scope right when a regen started (after the relearn process completed) and it had some soot - about 4.2 grams out 42 grams it should regen at. They did a manual cleaning to verify this, according to them. They've had my truck for about 45 days now.

Did the new DPF solve anything for you?
 
22PearlRamMegaHD said:
I am in the middle of a similar issue but it was 20-50 miles, some (most) days it was happening multiple times a day. All highway. They've bore scoped it a few times with a camera. Pre maf sensor change it appeared clean, but afterwards they did another bore scope right when a regen started (after the relearn process completed) and it had some soot - about 4.2 grams out 42 grams it should regen at. They did a manual cleaning to verify this, according to them. They've had my truck for about 45 days now.

Did the new DPF solve anything for you?
Click to expand...
After the DPF replacement the regen issue improved markedly. I could go several hundred miles of mixed driving before the gauge came off of zero. Then I would take a sustained highway drive either empty or towing a dump trailer full of gravel and it will passive regen back to zero in short order. 24 hour regens take about 15 - 20 minutes now as well. However, last week it went into an unscheduled regen at 4 engine hours/200 miles. The EVIC gauge is still on zero after 3 engine hours since that regen.

While the engine appears to be operating somewhat correctly after the DPF replacement, I still believe the DPF is a symptom rather than a cause of our frequent regen issue. I'm jumping on the Archoil bandwagon as well and we'll see how that goes.
 
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CaptainMike said:
After the DPF replacement the regen issue improved markedly. I could go several hundred miles of mixed driving before the gauge came off of zero. Then I would take a sustained highway drive either empty or towing a dump trailer full of gravel and it will passive regen back to zero in short order. 24 hour regens take about 15 - 20 minutes now as well. However, last week it went into an unscheduled regen at 4 engine hours/200 miles. The EVIC gauge is still on zero after 3 engine hours since that regen.

While the engine appears to be operating somewhat correctly after the DPF replacement, I still believe the DPF is a symptom rather than a cause of our frequent regen issue. I'm jumping on the Amzoil bandwagon as well and we'll see how that goes.
Click to expand...
Did you mean Archoil here?
 
mbarber84 said:
Unless there’s a hole in the DPF you shouldn’t see soot at the tailpipe. The only way soot appears there is if the DPF media or the pressure vessel fails in some manner and allows soot to bypass. (Which should be detected by the PM sensor at the back of the SCR and set off a DTC)

It would have been interesting to see pictures of that heat damage. That too is a rarity but something that should have DTC’s associated with it.
Click to expand...
There was definitely some bluing on a portion of the screen. It was a focused area on the lower right (IIRC) about the size of a nickel. I did try to get a photo, but none came out clear enough to see. The tech and I both would have liked to cut that thing open and see what the guts looked like, but they had to send it back intact. If it were a non-warranty issue I dang sure would have taken it home for dissecting.
 
CaptainMike said:
After the DPF replacement the regen issue improved markedly. I could go several hundred miles of mixed driving before the gauge came off of zero. Then I would take a sustained highway drive either empty or towing a dump trailer full of gravel and it will passive regen back to zero in short order. 24 hour regens take about 15 - 20 minutes now as well. However, last week it went into an unscheduled regen at 4 engine hours/200 miles. The EVIC gauge is still on zero after 3 engine hours since that regen.

While the engine appears to be operating somewhat correctly after the DPF replacement, I still believe the DPF is a symptom rather than a cause of our frequent regen issue. I'm jumping on the Amzoil bandwagon as well and we'll see how that goes.
Click to expand...
Just adding:
Keep in mind that when the dashboard gauge shows 0%, that’s not necessarily true zero. By the time you see movement on that gauge, you’re somewhere around 60% of the way to an active regeneration. Seems to fluctuate some but you get about 4 “notches” on that gauge. 60-70-80-90 etc. 90% seems to be right around the last notch before the bar reaches the 50% mark. You actually never see the bar hit 50% in most cases because the system triggers regeneration and switches to the “automatic exhaust system regeneration in progress” message before it actually moves.
 
CaptainMike said:
There was definitely some bluing on a portion of the screen. It was a focused area on the lower right (IIRC) about the size of a nickel. I did try to get a photo, but none came out clear enough to see. The tech and I both would have liked to cut that thing open and see what the guts looked like, but they had to send it back intact. If it were a non-warranty issue I dang sure would have taken it home for dissecting.
Click to expand...
Were there any DTC’s indicating an overheat event in the DPF?
 
CaptainMike said:
Yes, Archoil. Thanks for the catch, and I fixed it.
Click to expand...
Use the cleaner first, I’m on my second tank after the cleaner using the standard dose (not performance dose) and I still need highway time but it does passively regen easier. May try the performance dose at some point. Have a long trip with the camper in tow so passive regen won’t be an issue.
 
mbarber84 said:
Were there any DTC’s indicating an overheat event in the DPF?
Click to expand...
There was not. And thanks for the breakdown on the soot loading. I figured it was something like this, but I don't have the mind, patience, or inclination to puzzle it all out. I am envious, and thankful, of those of y'all who do.
Units said:
Use the cleaner first, I’m on my second tank after the cleaner using the standard dose (not performance dose) and I still need highway time but it does passively regen easier. May try the performance dose at some point. Have a long trip with the camper in tow so passive regen won’t be an issue.
Click to expand...
Thank you for the advice.
 
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