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Discussion Starter #1
I have an Edge Insight which shows the 'filter_load', but does anyone know what the numbers actually stand for? I've seen mine run up and down between 2.1 and 4.6, but I have no idea how full that is.

Anyone had an insight (or something) when the overhead showed 70%? What was the filter_load then? I'm guessing it's 1-10, but don't really know.
 

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Curious as well, it seems to be more of a counted over time number rather than a measured value.

Some with DPF deletes have reported seeing that number up in the 9s with no negative effects.
 

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Discussion Starter #3 (Edited)
I've been trying to decode the Chrysler specific PIDs used in these trucks using an ELM device and a program I'm writing. I can monitor all the standard obdii params plus a number of the Chrysler specific ones (regen desoot, desox, time since regen, etc.) that I've managed to decipher, but I'm having some trouble with the filter load. Looks like it's in the 2nd, 3rd, & 4th bytes of the data portion of the custom query with mode 0x21 and pid 0x4d, but I don't know if I've found the right formula. If you combine the three bytes ( byte1*65536 + byte2*256 + byte3) and divide by 32768, and then round it to 1 decimal, you get what 'seems' to equal Edge Insight's calculation of the filter load. But I'm not certain. I've watched it go up with normal driving and down with regens, but I was hoping someone could help fill in the blanks!

Currently I'm able to monitor up to about 20 parameters at a time, and it's dumping directly to an SQL database so that I can study and graph relationships later. I've captured a few regen sessions so far, but still trying to make sense of it all.

Interesting part is how quickly the filter load changes with different driving conditions. Edge only shows a rounded number that seems to change slowly, but the raw data changes much more rapidly with more than one decimal place of accuracy. That makes it more obvious how different driving styles affect the filter load.
 

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If the Edge reading never exceeded 5 I'd make a guess and say it's one of those voltage type sensors that reads 0-5 volts. That's a pure swag on my part.

Isn't what's being measured the differential pressure before/after the dpf? I would expect the instantaneous value to move rapidly all over the map because of the changes in exhaust volume. If the dpf remained in a constant state, say 50% clogged, the differential pressure would change dramatically when the driver put the pedal to the floor.

I wonder if regens could be triggered by conditions other than dpf backpressure. Maybe the O2 sensor acts as an indicator of NOX catalyst effectivness and triggers a regen if the ECU thinks the catalyst needs burning off even when the dpf is doing fine. I don't even know if the NOX catalyst actually needs "burning off" - this is all guesswork for me.
 

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It seems that the regens are mostly triggered (or not) by tracking temperatures in the DPF assembly, from what I've read most of the 1st generation fool boxes are just resistors that make the ECM think that the temperatures are over a certain point pretty much all of the time.

I noticed that in my Insight it lists the ReGen trigger as 4.5 but I usually get a regen at around 4.0 or a little lower, what is very interesting is that if I leave the truck parked for a few weeks I almost always get a regen within 5 minutes of getting on the freeway even if it had just completed one on the trip prior to being parked.
 

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Tracking on my Insight - the DPF load ( I think ) is a measurment of back pressure or soot build up within the filter. During Regen ( after the desoot stage) the DPF temps climb up into the 1100 degree range ( 1200 would be better but I can't get my 6.7 to generate enough EGT long enough to sustain - see old post from me on DPF and info about regen process) you can watch the DPF load drop. However, the total regen time is limited to protect the DPF itself from sustained high temps.

If you do a lot of city driving, the regen will attempt and fail ( you can track those with the insight as well). I have seen my Load score as high as 12.8 without any overhead system warning. I have seen it as low as 3.2 and still attempt to regen.

As far as I can tell there is no magic Load # that triggers regen. It does appear that if a reg cause teh load # to drop a certin % ( or # of points) that it counts it as sucessfull.

I have also read that driving with load can make the regen process more effective --- 1400 miles with a 4000lb trailer - no such luck... it tried several times but always quit mid process. I suspect that was because the DPF temps were too high during the desoot stage and the fuel simple "flash burned" as opposed to soaking into the existing soot.

BillG - does this make sense from your testing?
 

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Discussion Starter #7 (Edited)
My Insight says the regen trigger is 4.5 also, but I've kept the filter load below 4 (mostly), and it still seems to always want to do a regen. I've seen it try to do a regen at 2.9! Doesn't seem to pay any attention to the trigger.

I also read that you get a better regen under load, but it hasn't proven true for me. I seem to get the best regens at 60mph (I know the TSB says 50) without a load. With a load, or even just climbing a hill without a load, the cat temps drop fast when the extra fuel is spent maintaining speed. Sounds backwards, but we're talking drop from ~1200 to 900-1100, and the filter reduction slows. Almost seems like the extra fuel in the exhaust stroke becomes rationed when that fuel is needed instead for power - just a guess ofc!

There are also two kinds of regens that I see, and they seem to alternate. One regen does about a 20 mile DeSoot and then turns off, and it increments the Regens Completed number as though it was successful. But, it does nothing to the filter load. The 2nd type does a DeSoot for about 10 miles and then switches to a DeSOx for 15-20 miles. During the DeSOx, my filter load drops. Strange thing is that this type never increases the Regens Completed number.

The 'temperature below a certain point' concept needed for a regen makes sense with what I'm seeing. If I get on the hwy and run hard, it rarely does a regen. If I go through the city and catch a bunch of lights, it almost always starts a regen! So basically it only wants to do a regen when it can't succeed! Frustrating...

I read on another forum that the Insight filter load is supposed to represent grams of soot. I'm skeptical of that though because the filter load only decreases during a DeSOx - not a DeSoot.
 

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Casual reading on the MB BlueTec NAC+SCR system (which I think is the closest to what we have) suggests that one regen cycle cleans the Nox absorber and the other burns off the soot - I have noticed that I seem to get different turbo responses depending on which cycle is running, the cycle that doesn't decrement the DPF status (my Insight software is too old to show which cycle is running) makes for little boost unless I really get into it whereas the soot burning cycle makes boost very quickly with minimal throttle input - a very informative general regen post on a Ford forum suggested that this is one ways that the A/F ratio is controlled for regen.

Here is a bizarre one to ponder - the first part of my usual drive is a 10 mile downhill highway run at about 70 - 75mph, last week the Edge EGTs (DPF) shot up to regen temperature but the exhaust manifold EGT gauge hung at around 800 (usual ex manifold regen temps are in the 1300 range) this went on for 6 miles until the DPF EGTs dropped back to normal, the regen started up again normally once I got down to the flat ground.
 

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Discussion Starter #9
Casual reading on the MB BlueTec NAC+SCR system (which I think is the closest to what we have) suggests that one regen cycle cleans the Nox absorber and the other burns off the soot
Makes sense. I also found another Edge competitor offering a beta test of their product, and it showed three possible regen states: desoot, denox, and desox. I haven't been able to find that page since, but I know I saw it. My Insight only shows desoot and desox. I'm curious if there really are three, and if not, I wonder if Edge has them backwards (since Edge indicates desox lowers the filter load, but the filter load is supposed to be a measure of soot). The program I'm working on clearly shows the two triggers Edge is using for desoot and desox, but I haven't seen evidence yet of a third. (Although, there is so much data, truly a needle in a haystack.)

Here is a bizarre one to ponder - the first part of my usual drive is a 10 mile downhill highway run at about 70 - 75mph, last week the Edge EGTs (DPF) shot up to regen temperature but the exhaust manifold EGT gauge hung at around 800 (usual ex manifold regen temps are in the 1300 range) this went on for 6 miles until the DPF EGTs dropped back to normal, the regen started up again normally once I got down to the flat ground.
Wow, that is strange. Maybe the third mystery regen? ;)


Anyone with the shop manuals - do they show the Chrysler specific diagnostic codes and responses for the OBDII CAN bus?
 

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My Insight says the regen trigger is 4.5 also, but I've kept the filter load below 4 (mostly), and it still seems to always want to do a regen. I've seen it try to do a regen at 2.9! Doesn't seem to pay any attention to the trigger.

My regen trigger never moves from 4.5.

There are also two kinds of regens that I see, and they seem to alternate. One regen does about a 20 mile DeSoot and then turns off, and it increments the Regens Completed number as though it was successful. But, it does nothing to the filter load. The 2nd type does a DeSoot for about 10 miles and then switches to a DeSOx for 15-20 miles. During the DeSOx, my filter load drops. Strange thing is that this type never increases the Regens Completed number.

I've noticed that as well.

I read on another forum that the Insight filter load is supposed to represent grams of soot. I'm skeptical of that though because the filter load only decreases during a DeSOx - not a DeSoot.
Mine seems to decrease the regen load in desox at over 1100 deg.
 

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Makes sense. I also found another Edge competitor offering a beta test of their product, and it showed three possible regen states: desoot, denox, and desox. I haven't been able to find that page since, but I know I saw it.
I wonder if the Dashhawk will show the 3 possible regens... I've noticed that the online support for that product is a lot better than the Insight - mine still won't show the 2 that yours does and I updated it a couple of times.
 

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What Do The Numbers Mean?

hello folks, bill im not familiar with the insite monitors you guys are using, but i can only imagine the numbers your throwing out is equivelant to what is see on my starscan . under the starscan mobile desoot screen the value is called soot load based on delta. i would assume this "value" is calculated from the two pressure readings pre and post dpf/catalyst. this value may very well be calculated into grams given the known flow rate of the dpf and the amount of grams of soot it would take to provide a given pressure difference.i've noticed during mobile desoots that the soot load based on delta will be as high as 45 on a very restricted dpf and low as 2 on a non restricted dpf.also i've always noticed during a mobile desoot that the regen always starts off with a desoot mode and then goes to desox and denox last. then back to normal mode.hope this makes things clear as mud lol.
 

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Discussion Starter #13 (Edited)
hello folks, bill im not familiar with the insite monitors you guys are using, but i can only imagine the numbers your throwing out is equivelant to what is see on my starscan . under the starscan mobile desoot screen the value is called soot load based on delta. i would assume this "value" is calculated from the two pressure readings pre and post dpf/catalyst. this value may very well be calculated into grams given the known flow rate of the dpf and the amount of grams of soot it would take to provide a given pressure difference.i've noticed during mobile desoots that the soot load based on delta will be as high as 45 on a very restricted dpf and low as 2 on a non restricted dpf.also i've always noticed during a mobile desoot that the regen always starts off with a desoot mode and then goes to desox and denox last. then back to normal mode.hope this makes things clear as mud lol.
Thanks - that helps quite a bit especially since you just confirmed there is a denox as a third stage. I've had indications of that, but hadn't been able to find it or prove it yet.

The Edge only shows desoot & desox, but not denox, and it also shows the filter load. I'm guessing the filter load is intended to be the same as your soot load. I keep mine between 2 & 4 most of the time, but I didn't know the range. You mentioned seeing it as high as 45. Do you know what the soot load numbers are when the overhead says 70% (or higher) so that I can try to map the range to a formula?

Any chance the starscan shows the mode/pid combo that provides the data it formats for display?

I've got a laptop wired in using an ELM device, and I'm learning much more than I can get from the Edge. For instance, if I request a custom mode/pid of 0x21 / 0x48, I get a stream of 60 bytes of data. I've learned that bytes 47 and 49 tell me if a desoot or desox is in progress. Haven't found the denox yet. Does denox usually begin immediately after desox? Or does it start up after a 15 mile rest or something. That will tell me where to look in the volumes of data.

So far, I can track all standard obd info plus these Chrysler specific ones: time since last regen, regens completed, regens desired, filter trigger, filter load, desoot, desox, turbine speed, trans temp, & trans oil temp. I want more! Surely Chrysler makes this stuff available - I wonder how much?

The attached txt file is a sample of a logfile from my program showing a desoot started at 19:01:27.83 (byte 47). There's a lot more data there than I've figured out though.

Sorry for the looooong post!

p.s. I replaced the txt file with a new one - linux to windows end of line handling nailed it, but it should look proper now.
 

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BILL AFTER DESOX MODE DENOX USUALLY OCCURS WITHIN A MIN OR TWO BUT CAN ALTERNATE BETWEEN DENOX AND NORMAL MODE FOR A FEW MIN. KEEP IN MIND ALSO IM VEIWING WITH INFORMATION DURING A FORCED REGEN. I DONT THINK THE SEQUENCE IS ANY DIFFERENT DURING A NORMAL DRIVE CYLCE, I' HAVENT MONITORED IT UNDER A NORMAL DRIVE CYCLE.TO ANSWER THE second question , no my starscan does not give me any mode pin combo's . this in basically useless as a technician diagnoseing and repairing vehicles. this however would be used during engineering testing /authenticating of powertrain software development.i dont have access to that equiptment/software, sorry.as far as the additional info i can view... well there's lots of it , too much for me to list. but as far as pertaining to regens, there is also a estimated soot removal time counter which lessens during a forced mobile desoot it looks like this 258600 where I think the first two numbers are the estimated mins. i've noticed during a forced regen the first two numbers decrease roughly by minutes and never fully go down to 0 and after the regen is done and goes back to normal the numbers slowly climb back up a little while driving. think that covered everything, let me know if ya have any more ?'s. im somewhat familiar with these
 

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How do you guys like your insights?? Im looking for a gauge package which includes boost, tranny, pyro, and fuel pressure. I could care less about anything else. I dont wanna clutter up my truck with more crap. I already have enough stuff inside the cab as it is. I was thinking about the commander. i wouldnt mind something that is a code reader also.
 

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What is this ELM device? I've done a bit of work on my old 2nd gen with a laptop and a bunch of custom Linux programs I wrote. Now my 6.7L is just begging me to tinker with it!
 

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Discussion Starter #17
BILL AFTER DESOX MODE DENOX USUALLY OCCURS WITHIN A MIN OR TWO BUT CAN ALTERNATE BETWEEN DENOX AND NORMAL MODE FOR A FEW MIN. KEEP IN MIND ALSO IM VEIWING WITH INFORMATION DURING A FORCED REGEN. I DONT THINK THE SEQUENCE IS ANY DIFFERENT DURING A NORMAL DRIVE CYLCE, I' HAVENT MONITORED IT UNDER A NORMAL DRIVE CYCLE.TO ANSWER THE second question , no my starscan does not give me any mode pin combo's . this in basically useless as a technician diagnoseing and repairing vehicles. this however would be used during engineering testing /authenticating of powertrain software development.i dont have access to that equiptment/software, sorry.as far as the additional info i can view... well there's lots of it , too much for me to list. but as far as pertaining to regens, there is also a estimated soot removal time counter which lessens during a forced mobile desoot it looks like this 258600 where I think the first two numbers are the estimated mins. i've noticed during a forced regen the first two numbers decrease roughly by minutes and never fully go down to 0 and after the regen is done and goes back to normal the numbers slowly climb back up a little while driving. think that covered everything, let me know if ya have any more ?'s. im somewhat familiar with these
Awesome, thanks for the info! I'll have to try to find the denox indicator and the soot removal time counter in the data. I've noticed a couple of 3-byte counters that act similarly. Maybe I can find it just by comparing the decrease with the increase in time - deltas should about match. Does the minutes remaining decrease across all three stages, or does it just show the minutes remaining for the DeSoot?

During the DeNOx, do the CAT temps run as high as in a DeSoot & DeSOx?

Hope you don't mind the ?s, but I sure appreciate the info!

---

The ELM device is an IC that can translate OBD information to RS232 so that a PC can communicate with the vehicle's computer. I'm playing with an ELM327 usb from scantool.net
 

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I BELIEVE the estimated soot removal time goes down during all the modes but im not 100% sure. as far as temps go we basically only focus on temp sensor no.3 . once again im not 100% sure but i think the temp sensor 3 does show a higher than normal temp during desox and denox but not nearly as high as desoot mode. also i've noticed depending on the amount of soot stored in the dpf/catalyst the temps can vary . some regens i've seen as low as 1100 some as high as 13-1400 seems like the more soot the higher the temps go.i guess it would be interesting to do a data capture on my scanner during a regen. maybe I will sometime. hopefully i get sent to school on these soon so i can get a little inside scoop on a few ?'s. just as a tid bit we recently had some engineers from cummins come out and invited customers to our dealer to discuss issues they had with there 6.7 's. might want to keep an eye out from your dealer for an invite. they set aside a period of time for the technicians and they were pretty helpful in answering some of our ?'s and took a few suggestions from us on ideas as well.
 

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Discussion Starter #19
I BELIEVE the estimated soot removal time goes down during all the modes but im not 100% sure. as far as temps go we basically only focus on temp sensor no.3 . once again im not 100% sure but i think the temp sensor 3 does show a higher than normal temp during desox and denox but not nearly as high as desoot mode. also i've noticed depending on the amount of soot stored in the dpf/catalyst the temps can vary . some regens i've seen as low as 1100 some as high as 13-1400 seems like the more soot the higher the temps go.i guess it would be interesting to do a data capture on my scanner during a regen. maybe I will sometime. hopefully i get sent to school on these soon so i can get a little inside scoop on a few ?'s. just as a tid bit we recently had some engineers from cummins come out and invited customers to our dealer to discuss issues they had with there 6.7 's. might want to keep an eye out from your dealer for an invite. they set aside a period of time for the technicians and they were pretty helpful in answering some of our ?'s and took a few suggestions from us on ideas as well.
Thanks again. You've helped me a good bit. I'll keep an eye out for the cummins offer - I'd definitely be interested in contributing my $.02!

I'm looking at Chrysler's techauthority website - $20 for 24hrs. Hard to tell what's available there, but I'm thinking it has the info I need.
 

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Discussion Starter #20
How do you guys like your insights?? Im looking for a gauge package which includes boost, tranny, pyro, and fuel pressure. I could care less about anything else. I dont wanna clutter up my truck with more crap. I already have enough stuff inside the cab as it is. I was thinking about the commander. i wouldnt mind something that is a code reader also.
The Insight has been a great help to understanding everything. It gives a good indication of the DPF status and regen status (part of it I guess) plus all the standard stuff. It's a bit pricey, but you can configure 4 screens of 7 params each. It wasn't enough for me. I wanted to be able to compare 20-30 parameters at the same time and capture them for a fairly long interval to really analyze what's happening, and to get it I had to start work on my own software. The insight is a whole lot more compact and convenient than a laptop, though!
 
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