Cummins DPF Issue? Code SPN-3251

[TX Bella]

Driving our 2008 Dynasty 8.9 ISL. Left Navarre Beach yesterday, driving Hwy 87 towards I-10. After about 10 minutes (driving 45-50mph) a yellow check engine light came on, a few minutes late the DPF (Diesel Particulate Filter) came on and few minutes later the DPF light began flashing. Once on I-10 the engine became derated and the Stop Engine light turned on. We limped into a RV park in Milton, FL.

About a week ago we were delayed around 90 minutes very slow traffic under 5mph, for an accident on I-75.

Called Cummins in Mobile Alabama said it would be over a week before we can get in. Contacted Empire Truck Sales, Pensacola, said we could bring it in on Monday. I have a Mobile mechanic, Southern Commercial Diesel coming sometime today.

I have a code reader, Codes SPN3251 FMI16 and SID 324 FMI0 were displayed.

Is it possible to do a manual regeneration? I don’t see a manual regeneration button.

Any other thoughts or suggestions?

[Frank McElroy]

You would need the Cummins Insite software to do a stationary Regen.  Also, you should use large fans to cool the fiberglass around the DPF during a stationary Regen. 

However, something is generating soot.  Other trouble codes need to be checked. 

On your engine, a common problem that generates soot is a sticking VGT - either the actuator or turbo itself.  Could also be a dirty EGR system or a bad injector.  Not all of these will through a check engine light code. 

The shop will likely disconnect the DPF to see if the engine is generating soot.  If it isn't, they'll likely try a stationary Regen to get you back on the road so the engine can do a much better highway Regen. 

Also, ask the shop to look at the last ten stored regens to see if they have all been normal.  On a healthy engine you should go about 100 hours between regens and they should all be normal soot loadings.

[Tom Cherry]

4 minutes ago, Frank McElroy said:

You would need the Cummins Insite software to do a stationary Regen.  Also, you should use large fans to cool the fiberglass around the DPF during a stationary Regen.  However, something is generating soot.  Other trouble codes need to be checked.

Frank, as usual, is spot on.  The ISL's have NO MANUAL button.  The system was designed to do an AUTO Regen based on Engine Hours (100 I THINK).  I have the same engine as you and Frank, except mine does not have the "Jake Brake" hardware in the Head....doesn't matter.....SAME.  Frank scanned mine for me several years ago and the Regens were like clockwork.  

We have talked and my own "layman's observations" is that if you get a "Regularly Scheduled" regen light.....and are or have been driving around in stopped or slow traffic, you will need to keep driving, maybe downshifting to 5th to keep the RPM up.  My last one flashed several times and would stay on.  Frank's advice....DRIVE IT.  I had a trip planned and about 15 miles into it....REGEN....Downshifted and it stayed on for about 30 miles.  I have had the Regen light "Flash" many times over the years (I have 68K on it) after a long stint in slow traffic.  BUT, it goes away.  Only ONCE have I ever had a LONG (over an hour) REGEN......SO DRIVING (if you CAN) works....

Yours sounds like an issue and it needs PROFESSIONAL diagnostics....from a qualified shop.

Read the second page and Daryl Ammon's posts.  Really inciteful. Daryl made it all the way from CO to NC and was OK.  He did finally get a code a few weeks after that and had a sensor replaced.  Based on what he told me and Frank's account or explanation....he is probably OK and the defective sensor replacement sounded correct....he has about 65K on the engine.

I offer NO technical advice....except to have the engine scanned by a REAL TECH that has the Insite software and then get a diagnosis and a QUOTED cost.  You MIGHT want to post that information here before committing.....  LOTS of folks here with a vast array of knowledge.....  Always good to TRUST the Shop....but VERIFY what they want to do....  

[MyronTruex]

DPFs in those years had some serious issues. This was a new system and it had growing pains. Unfortunately, we customers paid for those growing pains. Based on a monster dumpster full of filters and comments from customers I met during my three-day downtime at a Cummins dealer. 

The breakdown was in 2015 with very low mileage on our 2008. We had less than 25K miles on it. I drove it hard and tried to make sure it did regens when they came on but ran into an issue in a long winding road situation where I could not get it up to a good speed. In a couple of days, my symptoms and codes were just like yours. 

My fancy top-of-the-line warranty company had some very fine print and the "emissions" systems were not covered. Cummins tried to clean the filter but it cracked and required a new one. Then they had to do multiple updates to the ECM. After that, the regens came more frequently and were entirely different in their presentations. Along with that, I lost some power. It was apparent in the go pedal something had changed. On flat ground pushing the pedal to the floor was just a request for some action.

Just a couple of years back I took the coach to the Cummins dealer in Tampa Fl and had an "uprate" done. It took less than an hour and the go pedal was awoken from a deep sleep. It will now actually accelerate. 

I think one of the causes of my DPF issues may have been getting some bad fuel that was not designed for this engine. I had to buy some fuel in an out-of-the-way podunk place. I had little choice. Somewhere in nowhere Maine. It was the next day that my problems began to rear its head. I tried to it regen running the high idle mode but that did not solve the issue. 

As we were heading to a Cummins dealer in New York with just 12 miles to go it went into limp mode on a very steep hill. I tried fuel filter changes but that did not help. Getting up that long steep hill with lights flashing and my wife driving the toad the New Yorkers kind of surrounded me with their flashers lighting the way to safety. Wow, I was deeply appreciative of their kind gesture. Making my way to a small parking lot the stop engine light came on and we were all done for the day. Seeing the million-dollar tow truck arrive was reassuring. It took over an hour for the driver to hook up and it was impressive to watch. Driveline disconnected, the tow part of his truck was adjusted by his remote control, and then actually measured the height of the vehicle while being towed to be sure he had clearances. He did an amazing job and reconnected the drive shaft at the dealership. The dealership had a 50 amp outlet where we stayed connected in the night since it is our home. They were a great facility.

Sorry, the saga is so long, but I highly suspect you need a filter but hopefully they can clean yours.

If anyone has regens that don't seem to act properly it could be a lot of money and misery saved if you take it in for manual cleaning.

 

[timaz996]

OMG, I'm so glad I don't have the emission stuff on my engine.

Tim

[bestins]

Has anyone used the pittsburgh power "max mileage"?  Supposed to lower the soot buildup. Thought this may help the soot issue in the future.

[Gary M]

I had the same issue two years ago in my 09. Mobil mechanic came out , removed it in parts. Took it to a shop that specializes in cleaning DPF’s. Reinstalled and $1500 later it’s back in and running fine.

[TX Bella]

Southern Commercial Diesel out of Crestview, FL (ph.#850-520-2797) came out to our site in Milton, FL. and connected the engine to the Cummins Insite computer program. He checked the codes, updated the computer programming and started a Stationary Regen. After about 30 minutes said it was making progress, after 45-60 minutes stated looked good (reading on Cummins Insite, a number he was looking at started at 84 was at 64 and needed to get to around 26). He finished and said you are good, told him I had a 10 hours to make it home Austin, TX.  He said we should not have a problem. We drove 300 miles yesterday to Cajun Palms Henderson, LA. no issues. 

The cost was $1000. not cheap but happy to be on the road, if it fixed the issue. He stated Cummins likely would have just changed the filter.

Asked since the Coach does not have a manual button if would help to have a shop do it every couple years, he said yes. Also stated he felt the cycle the onboard Regen process was not long enough to complete to process. Stated it was fixed on my my engine and could not be changed.(one persons opinion) 

He also stated that OTR Performance (otrperformance.com) has a device that plugs into the OBD and I could do a stationary Regen. Stated that it's common item with truckers. Looked at their website have not checked to see which item would be needed. I was going to conact him on Monday if I can not figure it out. (probably other companies have a similar item?)

Also, Cummins in Mobile, AL said it would be over a week look at it, Empire Truck Sales in Pensacola could look at on Monday sometime.

He also suggested sometime in the future to having the process of cleaning the DPF.

Heading to Austin this morning.

 

[Tom Cherry]

1 hour ago, TX Bella said:

Southern Commercial Diesel out of Crestview, FL (ph.#850-520-2797) came out to our site in Milton, FL. and connected the engine to the Cummins Insite computer program. He checked the codes, updated the computer programming and started a Stationary Regen. After about 30 minutes said it was making progress, after 45-60 minutes stated looked good (reading on Cummins Insite, a number he was looking at started at 84 was at 64 and needed to get to around 26). He finished and said you are good, told him I had a 10 hours to make it home Austin, TX.  He said we should not have a problem. We drove 300 miles yesterday to Cajun Palms Henderson, LA. no issues. 

The cost was $1000. not cheap but happy to be on the road, if it fixed the issue. He stated Cummins likely would have just changed the filter.

Asked since the Coach does not have a manual button if would help to have a shop do it every couple years, he said yes. Also stated he felt the cycle the onboard Regen process was not long enough to complete to process. Stated it was fixed on my my engine and could not be changed.(one persons opinion) 

He also stated that OTR Performance (otrperformance.com) has a device that plugs into the OBD and I could do a stationary Regen. Stated that it's common item with truckers. Looked at their website have not checked to see which item would be needed. I was going to conact him on Monday if I can not figure it out. (probably other companies have a similar item?)

Also, Cummins in Mobile, AL said it would be over a week look at it, Empire Truck Sales in Pensacola could look at on Monday sometime.

He also suggested sometime in the future to having the process of cleaning the DPF.

Heading to Austin this morning.

 

Good that you can drive.  Your comments are interesting.  Frank McElroy is our GOTO Guy.  Did you get the regen history from the CPU?  Did you read the comments that Frank and Daryl shared.  Daryl had a new DPF installed and did not go the "Stationary Regen".  He drove from Denver to NC and then eventually got a warning light and a shop that one of our members recommended did a complete scan and replaced a component in the engine/VGT system.  That was what Frank was alluding to.  Throwing parts or bandaids without really knowing or understanding the system is all to common....  We have several posts where one shop did this....and then another shop said that and finally, the poster found a good shop that did a comprehensive check....and FULLY UNDERSTOOD and THEN fixed it.

SO.....based on my experience and being a simplistic layman.....your engine has something amiss....as in the Regen's, per the CPU are either short cycling or there is a problem that is generating more soot.  There are way too many sensors involved and also way too many actuators or controls.  In Daryl's case, he has the issue, seemingly resolved and only time will tell.  IF that was not the ONLY problem....then the next item to be addressed will be the Turbine assembly itself.

FWIW, from discussion with Frank.....Cummins has stopped selling components that individuals or dealers can replace in the actual "Turbine".  Now you get a new (remaned??) turbine and it is installed as a unit.  The issue, as I understand it, there WAS a procedure for taking off the Turbine and then replacing the actuator....and you had to do it exactly per the Insite steps....and it was long and drawn out....and also involved put the actuator back on the turbine (after the Insite had calibrated it) on the Turbine....and Cummins supplied a template with marks.  Very meticulous individuals did that....but not every tech was that careful.  It APPEARED that the new actuators IMPROPERLY installed MAY have been a source of contention....and Cummins resolved that by not selling them.  That also cut out a MAJOR portion of the Tech's time.

Bottom LINE....  unless the tech found a specific cause, then the stationary regen started to clean the DPF.  If the component or connection or whatever (like a loose or leaky hose0 is STILL there and your get short cycling REGENS, it may come back.  How LONG???  Who knows. 

Don't know if you read the comments that Daryl offered.  The previous owner was incorrect and left the Exhaust Brake on full time.  Not only did that decrease (mine will cut 10% off the MPG when you leave the Exhaust Brake on and use the cruise), but it PROBABLY was the cause of his failure.  He now drives it responsibly and there was a bad engine sensor....and he has a NEW DPF.  SO, unless there is another component or issues with his Turbine....he will be good to go for at least 50 - 100K. 

NOW, there ARE some recommendations that every X (as in 100K), you need to have the DPF cleaned properly..  WHICH makes sense...but without knowing your mileage....that is an unknown.... 

No offense to the tech, but until you find someone that can identify the issue and not be biased by "Hey, you gotta do this every year", then you have dodged the bullet and can drive home.  BUT, the real issue does not seem to be addressed.  We have literally thousands of the ISL (I have one) in the group in the same age as yours.  The issues with the DPF are, overall, minimum.  YES....the DPF was an interim step that Cummins had to do to finally get to the DEF system.  My opinion of that is that I am glad I have the DPF....as mine works like it should.

Just my comments.....  Good Luck and keep up posted...

[MyronTruex]

Cummins had a bit of a steep learning curve with the DPF's. Trucks that had to idle for long times were very prone to issues. They said my engine had high idle times. That caught me off guard. I am not one to idle while breaking down camp for example. I learned however to use the high idle whenever possible and not annoying the neighbors.

     Thinking of the idle issue one has to look at the actual highway time versus time in traffic for example. Cummins did about six updates to my ecm and changed the cracked DPF and one sensor. They did a static regen after replacing the filter and sensor. Not sure why but am guessing it was just to check that the regen was working right. The regens since that time have been more frequent but mostly less time. I have seen regens be ten to fifteen minutes but have seen them go close to an hour. 

     I would suggest asking the Cummins folks at the gathering about running the exhaust brake if that can cause any issues. I run mine most of the time except in stop and go traffic. If we get stuck in a traffic stop such as an accident blocking things I will put the engine in high idle or shut ir off and run the generator to stay comfortable. I am very leary of high idle times.

     Sitting next to a gentleman at the Cummins dealer he was really frustrated. He was on his third DPF in a very short time and was being told of high idle times. I suspect Cummins figured out how to overcome the quick build up by running the regens more frequently.

      I believe I have seen a modification to install a manual control and believe there are RV's out there with it installed from the factory. I am happy with the way mine regenerates now and have been for 25K miles or so. We don't put a lot of miles on the coach overall so have little real long term experience.

     I have not heard of a lot of DPF issues since those years so Cummins sorted it out. Mine was an early 2008 so basically an experimental model so to speak.

     

[jacwjames]

I had to deal with early DPF installs on underground mining equipment to meet MSHA air quality regulations.  We started putting them on everything but soon learned that the equipment that was not run hard did not like the DPF filters, we had to change them out often.  The equipment that had a hard duty cycle performed well on.  We would check the exhaust back pressures and when they got to OEM max spec's we'd change the filters.   We invested $$$$ in a DPF filter cleaning system which consisted of a high temp oven and ten a vibrating table with air wash that would blow the filters clean.  This was all enclosed in sealed room as the soot that would be cleaned out of the filters was considered a carcinogen.  We spent several $M to get all the older equipment compliant that we could, older equipment we'd have to monitor and require employees to were respirator masks.   Most of the the newer equipment we purchased had the OEM installed systems, the performed better but still a RPITA.

So if you have a DPF system don't be afraid to run it hard, this helps burn off the soot. 

Edited January 8, 2023 by jacwjames

[Frank McElroy]

As with all new technology there is a learning curve on BOTH the OEM and the owner/operator. 

Sorry in advance for the long reply but some things need to be explained.

When I picked up my 2008 coach in April, 2007, it was one of the first 2008 models coming off the line with a DPF.  The engine ECM calibration was version #14.  In 2009, I updated the ECM calibration to version #32, then in 2017, I updated to version #57.  This is the latest and likely final revision to the ECM software for the Cummins ISL CM2150D engine.  So, you say why so many software updates?  Some are to edit the over 10,000 engine operating parameters, some are to add new features like an engine abuse history report, some address problems like turning on a false check engine light when there really isn't a problem.  The Cummins INCAL disk has a generic listing of what each update fixes.

Modern engines with DPF are incredibly sophisticated.  The ECM on an ISL has over 10,000 different parameters that need to be set for the proper operation of the engine at any operating temperature from cold start to overheat, at any engine load from idle to full load, at any altitude where it might be driven and then to do a DPF regeneration.  The ECM needs to control fuel injection up to 4 times per cylinder on each power stroke, the timing of these 4 separate injections (the last injection on an ISL is to add fuel during a DPF regen because there is no exhaust dosing injector like on the ISX), control the amount of EGR, the fuel rail pressure, and the turbo boost pressure to get a clean burn with minimal to no soot.

BTW those 10,000+ engine parameter settings do not include the programming code.  The ECM does not have a CPU processor and a computer program in the convention sense controlling the engine.  There is no CPU yet invented that would ever be fast enough.  Instead, the ECM uses hundreds of special processors call Programmable Gate Arrays (PGA).  Each of these are running simultaneously and for the most part running independently but talking with each other and controlling very specific engine functions.  The reason why I mention this is that all these engine operating parameters are established with dyno testing and field experience over time.  When Cummins identifies an issue even if in a specific application like a motorhome, fire truck, cement mixer, delivery van, etc. they will issue a calibration update.  If you had your engine serviced at a Cummins dealer, the first thing they would do is to reflash the ECM with the latest calibration software almost all of which are covered under warranty.

If you wanted to see the complete list of engine operating modes and the hundreds of program managers and all the 10,000+ operating parameters, get a copy of the Cummins Calterm software and upload your ECM calibration file to your laptop.  I did that on my ISL and the printout is just under 500 pages of text information. - That's right - 500 pages.

When running at highway speeds, the DPF is nice and hot and in effect doing a constant passive regeneration.  Sometime the DPF light might come on for a few minutes and then go off.  This just means that the pressure differential across the DPF is indicating that a regen might be needed but if the DPF is hot enough the pressure drops and the light goes out.  So, if the engine life is primarily highway, it is doing a passive regeneration until the ECM clocks about 100 hours of key on time from the last full regeneration.  That's when the DPF regeneration light will come on and stay on for about 30 minutes or more. 

The DPF light is telling the operator to drive under conditions to allow the DPF to regenerate.  So what does that mean?  These are the driving conditions that will suspend the actual regeneration cycle but still leave the light on - a lit check engine light, climbing a hill under full load, using the engine brake, coasting down hill with no throttle, speeds below about 35MPH.  Now. say you have the DPF light on and you reach your destination.  Not a problem but plan your next trip to be on the highway for a few hours.  If the pressures are high enough across the DPF, the regeneration will continue.  If the pressures are good, you won't see the DPF light for another 100 hours.

When DPF engines first came out, it wasn't always easy to find ULSD.  a couple of times, I could only find LSD at truck stops.  When that happened, sure enough after maybe 25 hour there would be a DPF regeneration because of soot loading.  Today all you can find is ULSD.

Idling is an issue because the DPF does stay hot enough to do the passive regeneration like it can at highway speeds.

If you like to drive the coach "hard" by being constantly on and off the throttle, speeds over 70 where your engine load is always high, you are going to be generating more soot and likely have more regen cycles.  City driving where the exhaust isn't getting hot enough to do passive regenerations like you can at a constant highway speeds between 60-65 will also cause more regeneration cycles.

A few comments on engine brake use.  I know some like leaving the engine brake on all the time so when they let off the throttle the engine brake comes on or they don't completely let off the throttle to keep the engine brake from coming on.  In my opinion, this is a poor practice especially on wet or icy roads.  The engine brake should be used when needed to slow down when going down a hill, exiting the highway or stopping .  Leaving the engine brake on all the time might be convenient but it will kill your fuel economy when it engages needlessly.  Think of it this way - leaving the engine brake on all the time would be like driving a car where your foot could only on the accelerator pedal or pressing on the brakes.  Yes, a diesel has no compression braking like a car but don't force the VGT into a braking mode every time your foot is off the throttle.  When you need engine braking, then turn it on to supplement the service brakes.

Now, let me say a few words about engine load.  Our 8.9 liter ISL engine can generate a little over half the power of an OTR 15 liter ISX.  Our coaches weigh about half that of a fully loaded 80,000lb 18 wheeler.  If your the kind of driver that likes to climb long grades at full throttle at highest gear lowest RPM and max speed, and pass every 18 wheeler doing it, that's not doing anything for the longevity of the engine and turbo.  On long grades, drop a gear, climb the grade slower with higher RPM and less engine load - your engine and your turbo will be a lot happier.

 

[Tom Cherry]

Frank McElroy said....

A few comments on engine brake use.  I know some like leaving the engine brake on all the time so when they let off the throttle the engine brake comes on or they don't completely let off the throttle to keep the engine brake from coming on.  In my opinion, this is a poor practice especially on wet or icy roads.  The engine brake should be used when needed to slow down when going down a hill, exiting the highway or stopping .  Leaving the engine brake on all the time might be convenient but it will kill your fuel economy when it engages needlessly.  Think of it this way - leaving the engine brake on all the time would be like driving a car where your foot could only on the accelerator pedal or pressing on the brakes.  Yes, a diesel has no compression braking like a car but don't force the VGT into a braking mode every time your foot is off the throttle.  When you need engine braking, then turn it on to supplement the service brakes.

 

This, to me is a major misconception and we have had folks that have self inflicted damage to their engines and emission systems.  I sort of equate it to this....  If Cummins wanted the VGT or Exhaust Brake on at all times, then it would have been very simple to use a latching relay and when you started the engine....BINGO it was on.  Again....we have many folks that were told or thought that keeping it on was required.  Based on talking to them offline and also Frank, I think this misconception ought to be cleared up.  I agree with Myron that it would be a good GROUP discussion.  

However, I can make this statement without fear of contradiction.  Early on in our first major trip I came back across the Canada/US border and had to use the Exhaust brake to slow down.  Then, I left if on.  I had reset one of my 4 trip minders....and when I checked the fuel mileage, it was 10% less.  The reason....the Cruise, with the Exhaust Brake ON, operates in a narrow band....so the ECM or Throttle Body Device is constantly accelerating and then decelerating.  It is also annoying.  NOW, since Monaco and Cummins never had the same system on a MH, OTHERS may not work that way.  I can engage the cruise....and when I tap the brakes.....the CRUISE stays on.  No matter IF the Exhaust Brake is ON or OFF.  Frank's Dynasty is different.  So, one rule or cookie cutter does not fit all.

I read a bunch of posts prior to discussing with Frank....as I knew his thoughts and explanation.  The bulk of the posts, and I don't mean to demean anyone, is ....YESSIIR....I turn that sucker on because if I didn't, it would crap up.  Drives like a dream...  There is NO real technical explanation as to WHY....and again, if Cummins wanted it on full time....then a relay.

If you read the manuals, it is to be used as auxiliary braking and provides a great tool to keep from damaging the service brakes.  I do USE MINE....so much so that my "Red Plastic" Actuator BROKE and I replaced it.  BUT, I think ahead and use it and when I come up on a ramp the top.....before I pull out, I turn it off.

That's my take on it....  We Moderators want to have the best and most accurate information out here so folks don't make mistakes or have issues.  Running the Exhaust Brake, based on the issues we have had, is a fine way to do damage....which can be expensive...

 

[Frank McElroy]

5 minutes ago, Tom Cherry said:

Frank McElroy said....

A few comments on engine brake use.  I know some like leaving the engine brake on all the time so when they let off the throttle the engine brake comes on or they don't completely let off the throttle to keep the engine brake from coming on.  In my opinion, this is a poor practice especially on wet or icy roads.  The engine brake should be used when needed to slow down when going down a hill, exiting the highway or stopping .  Leaving the engine brake on all the time might be convenient but it will kill your fuel economy when it engages needlessly.  Think of it this way - leaving the engine brake on all the time would be like driving a car where your foot could only on the accelerator pedal or pressing on the brakes.  Yes, a diesel has no compression braking like a car but don't force the VGT into a braking mode every time your foot is off the throttle.  When you need engine braking, then turn it on to supplement the service brakes.

 

This, to me is a major misconception and we have had folks that have self inflicted damage to their engines and emission systems.  I sort of equate it to this....  If Cummins wanted the VGT or Exhaust Brake on at all times, then it would have been very simple to use a latching relay and when you started the engine....BINGO it was on.  Again....we have many folks that were told or thought that keeping it on was required.  Based on talking to them offline and also Frank, I think this misconception ought to be cleared up.  I agree with Myron that it would be a good GROUP discussion.  

However, I can make this statement without fear of contradiction.  Early on in our first major trip I came back across the Canada/US border and had to use the Exhaust brake to slow down.  Then, I left if on.  I had reset one of my 4 trip minders....and when I checked the fuel mileage, it was 10% less.  The reason....the Cruise, with the Exhaust Brake ON, operates in a narrow band....so the ECM or Throttle Body Device is constantly accelerating and then decelerating.  It is also annoying.  NOW, since Monaco and Cummins never had the same system on a MH, OTHERS may not work that way.  I can engage the cruise....and when I tap the brakes.....the CRUISE stays on.  No matter IF the Exhaust Brake is ON or OFF.  Frank's Dynasty is different.  So, one rule or cookie cutter does not fit all.

I read a bunch of posts prior to discussing with Frank....as I knew his thoughts and explanation.  The bulk of the posts, and I don't mean to demean anyone, is ....YESSIIR....I turn that sucker on because if I didn't, it would crap up.  Drives like a dream...  There is NO real technical explanation as to WHY....and again, if Cummins wanted it on full time....then a relay.

If you read the manuals, it is to be used as auxiliary braking and provides a great tool to keep from damaging the service brakes.  I do USE MINE....so much so that my "Red Plastic" Actuator BROKE and I replaced it.  BUT, I think ahead and use it and when I come up on a ramp the top.....before I pull out, I turn it off.

That's my take on it....  We Moderators want to have the best and most accurate information out here so folks don't make mistakes or have issues.  Running the Exhaust Brake, based on the issues we have had, is a fine way to do damage....which can be expensive...

 

A few comments.

There are many engine parameter setting that can be changed using the Insite software.  Monaco elected to use none of them.

Yes, Cummins does have an option to automatically turn on the engine brake if the throttle is released.  Some fleets wanted that feature.  I think it's a bad practice but that's my opinion.

The cruise control has a feature to operate the Jake brake on low when X MPH above the cruise set speed and Jake brake on high when XX MPH above the set speed.  Those values can be programmed into the engine ECM using Insite software.  So let's say you set the cruise at 62 MPH and the low cruise Jake brake is set at +5 and the high Jake brake at +7.  That means above 67 MPH the low Jake brake would come on.  If above 69 the high Jake brake would come on.  Once the speed returned to below the Jake set point speeds the Jake would turn off and cruise at 62 would return.  Monaco didn't use that feature.

[MyronTruex]

Outstanding information Frank. Thanks for such a great effort. I understand my system better than ever. 

I did get a load of fuel that was not ULSD. My problems began shortly thereafter and I thought that might be the cause.

However, I have a little confession and want your opinion on how that device worked. I had a DIGICRtv module inline with one of the cables. I'm not sure what it did but the increase in HP and torque was dramatic. I had it dynoed in Oregon and it was truly amazing. I was never able to run it on it's highest setting because it would go into limp mode if I tried to accelerate too hard.

I loved the performance and the fuel economy actually went up.

After the bad DPF replacement, because it cracked during cleaning, I decided to retire the module. The reprogramming of my ECM caused me to lose 1mpg and it then accelerated like a slug. It was hard to get out of my own way.

     After several years of this annoying lack of power I had it uprated to 450 hp at a Cummins facility. It woke up the acceleration once again but the mileage did not change. It was never as powerful as when the chip was installed. 

    I'm not concerned about the mileage issue, nor the lack of power compared to when the chip was installed.

What I am wanting to know, can you explain what you think it might have been doing? I believe it was in a cable that fed the fuel system. 

Thanks

[TX Bella]

Made it home with no problems which was my original goal.

I had very little knowledge about a DPF 3 or 4 days ago today, I’m still learning. The HEST Dash Light came on a couple times for 10-15 minutes during our 700 mile trip home. The next step is to determine the cause of the DPF issue.

The tech said he would email me the Cummins Insite EIF file Monday.

Thanks for everyone input.

[Frank McElroy]

12 minutes ago, TX Bella said:

Made it home with no problems which was my original goal.

I had very little knowledge about a DPF 3 or 4 days ago today, I’m still learning. The HEST Dash Light came on a couple times for 10-15 minutes during our 700 mile trip home. The next step is to determine the cause of the DPF issue.

The tech said he would email me the Cummins Insite EIF file Monday.

Thanks for everyone input.

If you get that Cummins Insite EIF file, please send it to my email address -  fcmcelr@yahoo.com.  I can read the file and send you back a PDF file that you can read.

[Tom Cherry]

7 hours ago, myrontruex said:

Outstanding information Frank. Thanks for such a great effort. I understand my system better than ever. 

I did get a load of fuel that was not ULSD. My problems began shortly thereafter and I thought that might be the cause.

However, I have a little confession and want your opinion on how that device worked. I had a DIGICRtv module inline with one of the cables. I'm not sure what it did but the increase in HP and torque was dramatic. I had it dynoed in Oregon and it was truly amazing. I was never able to run it on it's highest setting because it would go into limp mode if I tried to accelerate too hard.

I loved the performance and the fuel economy actually went up.

After the bad DPF replacement, because it cracked during cleaning, I decided to retire the module. The reprogramming of my ECM caused me to lose 1mpg and it then accelerated like a slug. It was hard to get out of my own way.

     After several years of this annoying lack of power I had it uprated to 450 hp at a Cummins facility. It woke up the acceleration once again but the mileage did not change. It was never as powerful as when the chip was installed. 

    I'm not concerned about the mileage issue, nor the lack of power compared to when the chip was installed.

What I am wanting to know, can you explain what you think it might have been doing? I believe it was in a cable that fed the fuel system. 

Thanks

Myron, 

Not an expert like a Frank, but I have 4 trip minders that show hours, miles, average speed and gallons.  As I said, I meticulously use them for experimentation.  On the same stretch of a long trip, I have verified my comment.  The Cruise with the Exhaust Brake on will cut about 10% off your MPG compared to running as recommended and NOT having the Exhaust Brake on 100%.  I frequently make a 100 mile run to the beach on an interstate.  Just for kicks, I do the experiment every few years.  I am NOT a mileage fanatic.  I have a lower rear end ratio than Frank, and probably you have.  My 5-6 shift is due to the Monaco/Cummins/Allison agreed to parameters to shift up when the sweet spot (max torque @ 1250 RPM.  So I shift higher than the folks with higher ratios.  I played around with the parameters and came up with the 5-6 shift for Frank’s Dynasty….so, mathematically it works.  I set my cruise on 63 and used the economy setting and on most stretches, even a little up and down, it will stay in 6.  If it keeps downshifting….I bump up the set point 1 MPG.

That’s my take on it and why I am a proponent of leaving the exhaust brake off and coasting and planning ahead…and I don’t worry about mega $$$$ Engine issues.

52 minutes ago, TX Bella said:

Made it home with no problems which was my original goal.

I had very little knowledge about a DPF 3 or 4 days ago today, I’m still learning. The HEST Dash Light came on a couple times for 10-15 minutes during our 700 mile trip home. The next step is to determine the cause of the DPF issue.

The tech said he would email me the Cummins Insite EIF file Monday.

Thanks for everyone input.

My observation.  Assuming we are talking about the same light that comes on during a Regen…. My last one was interrupted.  During a few miles of urban it flashed.  Got on the interstate for about 100 miles.  About 10 miles….regen light.  I downshifted to 5 and bumped up my speed from 62 to 64/65.  Light stayed on for maybe 15 miles.  OFF…so back to 62 and 6th gear.  Maybe another 10-15 minutes….ON again. Bump speed and downshift.  I can’t remember if it did it again…. I back calculated the hours using a little Kentucky windage.  It WAS time, based on the 100 hour clock.

I would THINK that your rig was starting to feel like its old self….  BUT….it you were getting soot from a faulty component, then it was trying to keep it’s underwear clean.

Frank is a resource beyond all understanding.  Work with him and then you will know….

Good Luck….

PS, read Daryl’s adventure…..it is also insightful.

[Frank McElroy]

15 hours ago, myrontruex said:

Outstanding information Frank. Thanks for such a great effort. I understand my system better than ever. 

I did get a load of fuel that was not ULSD. My problems began shortly thereafter and I thought that might be the cause.

However, I have a little confession and want your opinion on how that device worked. I had a DIGICRtv module inline with one of the cables. I'm not sure what it did but the increase in HP and torque was dramatic. I had it dynoed in Oregon and it was truly amazing. I was never able to run it on it's highest setting because it would go into limp mode if I tried to accelerate too hard.

I loved the performance and the fuel economy actually went up.

After the bad DPF replacement, because it cracked during cleaning, I decided to retire the module. The reprogramming of my ECM caused me to lose 1mpg and it then accelerated like a slug. It was hard to get out of my own way.

     After several years of this annoying lack of power I had it uprated to 450 hp at a Cummins facility. It woke up the acceleration once again but the mileage did not change. It was never as powerful as when the chip was installed. 

    I'm not concerned about the mileage issue, nor the lack of power compared to when the chip was installed.

What I am wanting to know, can you explain what you think it might have been doing? I believe it was in a cable that fed the fuel system. 

Thanks

There are a lot of "fixes" and shops claiming they can reprogram the engine ECM to in effect provide more power without EGR or DPF issues.  In my opinion, none of them get it right.  They all go after the quick fix to trick the engine to run with more power or faster throttle response.  Yep, they might look great on a dyno but ultimately you are shortening engine life.

Folks would say that the ECM update fixed the check engine light.  Yep, the update turned off the check engine light manager so if there was a problem there would be no check engine light.  Then they also often would turn off the engine derate manager.  So, if the engine would normally derate because of an issue, the engine simply wouldn't derate.  The owner/operator thinks everything is just fine but they are actually destroying their engine and not knowing it.

You are correct in thinking that when you press on the throttle you are doing nothing more than to tell the engine ECM that you want higher RPMs.  That's exactly what happens.  The ECM takes the throttle input and adjusts fuel rail pressure, EGR, turbo boost and fuel injection to increase engine RPM at the fastest programmed rate depending on which engine operating mode it is running in such the it will rev up at the fastest rate but generate the least amount of soot.

Over the years, there have been devices out there designed to trick the engine into running under conditions designed to put it in an operating mode that isn't the mode it is really running in to in effect trick the ECM into not doing things like opening the EGR.  Then, they go into the ECM programming using the Cummins Calterm software and edit certain manager settings, like turning off the manager that controls rapid throttle changes to give the feel of faster throttle response while generating more soot, or adding more turbo pressure sooner and higher commanded fuel pressures to generate high HP.  In my opinion, none of these changes are effective and ultimately you will end up in either a failed DPF or major engine damage from high heat in the turbo, cylinder wear, burned pistons or a blown head gasket.  There is no internal secret setting to run these engines in a non-EGR mode under all operating conditions.  To accomplish this all the commanded fuel pressures, turbo boost pressures, egr settings, fuel injection rates and injection timing would all need to be changed to run the engine without oxygen depleted EGR gas and not shorten the engine life.  In my opinion, it's best to stay with the calibration software designed for the engine.

When the ECM program is edited using Calterm software, the actual ECM software code isn't changed.  So, when Cummins went in to do an update with a new software calibration, Insite told the tech that the software was up to date.  But when Cummins loaded a calibration for a 450PH engine, it in effect fixed all the bad parameters someone else entered.

In one of my replies, I mentioned that one of the software updates, Cummins corrected an error it had in calculating fuel economy.  You mentioned that you were seeing higher MPG.  I'm wondering if you verified this by tracking mileage based on tank fueling.  

When I first got my coach, I ran it for a few years with software version 14.  If you look at my fuel log (Aladdin is the engine ECM MPG) for about the first 25 fill-ups, the engine ECM was showing about 10-15% better fuel economy compared to actual tank MPG.  ECM software update #32 corrected that problem and now the actual tank and ECM MPG number basically match.  (Note - all the tank numbers were corrected for generator and aquahot use.)  So, that happened - Cummins missed adding in one of the 4 fuel injection pulses when calculating the MPG fuel economy.  I remember back around 2009 when Cummins was updating the ECMs and folks on all the forums were in a huge outrage saying that the new updates were killing fuel economy.  They didn't know what they were talking about and never actually measured real MPG based on tank fueling.

Hope you find all this information helpful.

[MyronTruex]

Wow, fantastic information. I have always done the manual calculations for fuel mileage to compare to the computer. The computer has seemed to be spot on but I have not done enough real driving since the uprate to 450 hp to know my new mileage.

That device that I plugged in did not reprogram the ECM. At least I do not think it could. It was not plugged into the "obd" port. I know, its called something else on the diesel but having a brain issue. 

The device had a Y cable and the module had various level settings. I don't think they make them anymore. I am happy with my 450 hp uprate and know I could have gone for more but it would have taken some other parts. 

My RV is rather heavy and I tow a full size pickup. I'm close to 40K lbs. I suspect the tile floor adds 2K lbs by itself. 

I remember the complaints of loss of mileage as you mentioned. 

Just as a side note. I changed out my fan blades not long after buying the RV. The original roared and took a lot of power to drive it. It was amazing the difference going downhill that the old fan helped the descent. The new fan has far less drag and the mileage improved about .5 mpg. 

[96 EVO]

Myron, I recall reading your post's back when you had your DPF replaced, and ECM updated.

The thought of possibly losing power, and fuel mileage, freaked me out enough, I've never taken my coach to Cummins for an update!

Quite possibly running the original ECM programing.

[Frank McElroy]

1 hour ago, myrontruex said:

Wow, fantastic information. I have always done the manual calculations for fuel mileage to compare to the computer. The computer has seemed to be spot on but I have not done enough real driving since the uprate to 450 hp to know my new mileage.

That device that I plugged in did not reprogram the ECM. At least I do not think it could. It was not plugged into the "obd" port. I know, its called something else on the diesel but having a brain issue. 

The device had a Y cable and the module had various level settings. I don't think they make them anymore. I am happy with my 450 hp uprate and know I could have gone for more but it would have taken some other parts. 

My RV is rather heavy and I tow a full size pickup. I'm close to 40K lbs. I suspect the tile floor adds 2K lbs by itself. 

I remember the complaints of loss of mileage as you mentioned. 

Just as a side note. I changed out my fan blades not long after buying the RV. The original roared and took a lot of power to drive it. It was amazing the difference going downhill that the old fan helped the descent. The new fan has far less drag and the mileage improved about .5 mpg. 

I looked up the description of the DIGICRtv modification.  What it says is that it adjust injector timing.  More than likely based on where it is plugged in is that it is telling the ECM that the fuel pressure is too low, so the ECM ups the fuel pressure.  When fuel pressure is higher, more fuel is injected.  This generates faster throttle response and more power but also more soot because you are running rich.  The ECM also will say that you are running better MPG than actual fact.  Not surprising this would cause lots of DPF regens.

[Tom Cherry]

1 hour ago, Frank McElroy said:

I looked up the description of the DIGICRtv modification.  What it says is that it adjust injector timing.  More than likely based on where it is plugged in is that it is telling the ECM that the fuel pressure is too low, so the ECM ups the fuel pressure.  When fuel pressure is higher, more fuel is injected.  This generates faster throttle response and more power but also more soot because you are running rich.  The ECM also will say that you are running better MPG than actual fact.  Not surprising this would cause lots of DPF regens.

From a layman’s perspective this “trick” has issues….and is not advised.  It reminds me of an acquisition trip that myself and one of the design engineers made to a remote small town in CA that was a 5 hour drive northeast of LA.  We were a major supplier of carburetors to Ford and we were diversifying as we knew EFI was coming and we would loose our major product line.  We were working on rebuilding carburetors or “remanning” them as well as supplying kits….and also making other carburetors like the Weber High Velocity (Stack) units.

The owner had a small shop and 3 test vehicles.  We drove off in one and the engineer says to me….well the evaluation is over….and pulled to the side of the road.  The BIG 2 barrel carburetor was like a commode.  When you pushed the accelerator there was a “trick throttle” linkage that went from idle or “off idle - low speed’ immediately to WOT (Wide Open Throttle). Thus, you had the feeling of unbelievable performance.  We had them ship in a unit and fabricated a test stand manifold.  It was no better than our own AFB or the GM QuadraJet….we passed on buying,

My grandson wanted a newer car and we found a Subaru WRX.  I was the “tech” consultant and played with the driving modes.  It has a “track” model. When you put it in that mode and press the accelerator and it gets above 1000 RPM (subjective) the turbo kicks in and it will really “jolt” you…especially for a 4 banger.  He is attending college in the NC mountains and the keeps it in the normal or default mode due to winter conditions.  My C7 Vette as a “Track” mode….and changes throttle response and the power steering.  

BOTH of these cars were designed with these modes and will still meet emissions standards and also NOT over Rev or damage the engine.  I did chuckle when Frank described the “system”…

[MyronTruex]

Great information. Now what does the "sport mode" in my F150 actuall do besides eat tires and put smiles on my face?

Great information on the Digi device. I suspected the curiousity would get you to research it. It put a smile on my face for sure when trying to get up steep hills. The Grapevine in Calif was a real test and topping the mountain at 50 mph was amazing. 

I want longevity over speed these days so the 450 hp will have to do. Shedding the F150 would help a lot of course. 

[Tom Cherry]

1 hour ago, myrontruex said:

Great information. Now what does the "sport mode" in my F150 actuall do besides eat tires and put smiles on my face?

Great information on the Digi device. I suspected the curiousity would get you to research it. It put a smile on my face for sure when trying to get up steep hills. The Grapevine in Calif was a real test and topping the mountain at 50 mph was amazing. 

I want longevity over speed these days so the 450 hp will have to do. Shedding the F150 would help a lot of course. 

Sport Mode

This mode increases accelerator response and provides sportier steering feel on Ford F-150. The powertrain system holds onto short gears longer, helping your vehicle accelerate faster. The four-wheel-drive auto is the default four-wheel-drive mode

Trick throttle, different shift points and changes the ratio in the electric power steering.  If I had the Electromagnetic shocks in my Vette, it would change the compression/extension rates…..

Safety TIP of the day.  Never attempt a “gag selfie” of a passenger hanging on for dear life when his daughter is driving a Subaru WRX for the first time and marveling at the handling and acceleration BEFORE i set it to default. A quick left turn will hurl your cranium into the B pillar and you have another reason to not shave your head as all the times you got hit there have left it like a moonscape.  My DW says that if I ever start to be follicle challenged, she is going to enroll me in Hair Club for Men as my scalp is dented and looks like an amateur hammer job on a fender….LOL!