DPF and Automatic Regeneration Process Questions

[StevenHodgkins]

That’s passive regen and normal when DPF temps exceed 600-650°F.

Generally automatic regen is the same as active regen.

Seems like it’s good and operating as it should. Really I need to quit watching it! I’ve been an Equipment operator for years and I can’t help but pay attention to what my vehicles are doing.

 

[Ozymandias]

Like said, the days of the teething problems are over.
The system works as desired now.

 

[Hoefler]

A 24 hour regen cycle makes no sense. If you have it up to tempt and it is in continuous passive regen, the is no need for it to do an active regen wasting fuel. Active regen is for the times the exhaust does not get hot enough for long enough to stay clean.

 

[AH64ID]

A 24 hour regen cycle makes no sense. If you have it up to tempt and it is in continuous passive regen, the is no need for it to do an active regen wasting fuel. Active regen is for the times the exhaust does not get hot enough for long enough to stay clean.

It does make sense, it ensures the DPF is still cleaned at higher than passive regen temps to increase service life. It does get it cleaner than passive regen alone, and I can see that in the readings on my CTS3.

Either way, it happens on your truck every 24 hours of engine run time.

 

[cricha]

It does make sense, it ensures the DPF is still cleaned at higher than passive regen temps to increase service life. It does get it cleaner than passive regen alone, and I can see that in the readings on my CTS3.

Either way, it happens on your truck every 24 hours of engine run time.

AH64ID - I have a CTS 3 as well and just finished an active regen. dash totalizer says 99 total hours of run time. On my CTS 3 I have it set to show me regen on/off and the percentage of soot. A regen is triggered when the percentage number gets to 100%, and then when it is done, the percentage is at 40-42%. This time the regen was done mostly on the freeway @60-65 mph. Ive never seen the arc graph on the dash show anything. Are you seeing numbers on your CTS that resemble what I'm seeing? I'm not exactly sure what the percentage number on the CTS represents after reading this string. Can you shed some light? THANKS!
an edit - I just went out and checked the run time, and saw the percentage number on the CTS is showing 4%.

 

[AH64ID]

AH64ID - I have a CTS 3 as well and just finished an active regen. dash totalizer says 99 total hours of run time. On my CTS 3 I have it set to show me regen on/off and the percentage of soot. A regen is triggered when the percentage number gets to 100%, and then when it is done, the percentage is at 40-42%. This time the regen was done mostly on the freeway @60-65 mph. Ive never seen the arc graph on the dash show anything. Are you seeing numbers on your CTS that resemble what I'm seeing? I'm not exactly sure what the percentage number on the CTS represents after reading this string. Can you shed some light? THANKS!
an edit - I just went out and checked the run time, and saw the percentage number on the CTS is showing 4%.

Yes, that's similar to how mine works. The number immediately following an active regen usually reads in the 35-45% range, but the next time I start it shows a much lower number like you saw. The lower the number the cleaner the DPF is following the regen, yours is quite clean but it should be with only 99 hours on the truck.

The percentage shows you how close you are to a regen, and it's driven by two different things. Time and soot, so it only shows whichever one is higher. What I have found is that for the first ~12 hours it bounces around based on soot loading, and then time is the higher reading so it steady's out and goes up 0.4% every ~5 minutes.

I don't have the regen on/off showing because there is an LED that will light up at the top of the screen and the percentage lets me know when it's going to happen.