Can A Regen Misfire???

[dquaney]

My '08 4500 now has 68,000 engine troublefree miles on the odometer. I was pulling a heavy load of hay through Oklahoma City 2 nights ago and stopped for fuel. I had stopped at the pump and started pumping fuel with it idling when it looked like my exhaust pipe turned into a mosquito fogger for what seemed like an eternity but was only about 30 seconds. I checked the oil and water which were both fine. The motor sounded normal. Everyhting appeared normal, with no check engine lights and the system reported normal, so I went on. The trip was another 450 miles with no problems. The only thing I could come up with was the regen initiated and did not burn when it hit the DPF. Is this possible?



Dan

 

[FATCAT]

Was it black smoke or white smoke?



If black (dark gray), then maybe it did go into regen but since the exhause was cooling down the diesel going down the pipe was not burnning at a high enough temp in the DPF and then you get the black/dark gray smoke (just like unburnt fuel when you punch it on the old 12 valvers).



Do you have a Edge Insight (Monitor only)? It will tell you when you go into regen. I have one and it is definitely one of the best things I have ever bought for any of my trucks. I like to know whats going on and not have any mysteries.

 

[dquaney]

Fatcat,



It was clearly white smoke. My thoughts were the same about the color but then thought OK the old mechanical tractors blow white smoke at cold weather start up which would be unburned fuel. The similar thing that would have happened to my 4500. I don't know for sure. I don't claim to be an expert on anything but would like to find out if this is what happened as I am almost ready to put on the H&S delete kit. I may not want to do that right now if I am losing a head gasket.

 

[Bob4x4]

Was it black smoke or white smoke?



If black (dark gray), then maybe it did go into regen but since the exhause was cooling down the diesel going down the pipe was not burnning at a high enough temp in the DPF and then you get the black/dark gray smoke (just like unburnt fuel when you punch it on the old 12 valvers).



Do you have a Edge Insight (Monitor only)? It will tell you when you go into regen. I have one and it is definitely one of the best things I have ever bought for any of my trucks. I like to know whats going on and not have any mysteries.

You should never see black smoke out of a dpf truck unless the dpf has failed... ... .

 

[HBarlow]

Dan,

My egt gauge tells me that if my truck is in the regen mode and I stop and shift into park position and allow the truck to continue idling (or fast idling) the ECM terminates the regen. I know this because I can watch egt slowly decline from 600* to 800* when I shift into Park position to below 400* over a period of three or four minutes.

I have never jumped out to look at the exhaust pipe to see if I could see any smoke of any color but have never seen any emission from this truck on acceleration or at idle in the outside rear view mirror.

Can't offer any explanation for what you saw but I doubt it is a headgasket failure.

Please post your results and opinions here if you install the delete kit.

 

[dquaney]

Harvey



I didn't have to jump out to see any of this. The attendant in the station thought my load of hay was on fire. You could have seen this if you were driving by on I-35. This is why it is so strange. This is not something that you had to be out there sniffing on the exhaust pipe to notice.

 

[HBarlow]

Dan,

Well, I guess you are breaking new ground. I have not seen or heard of this but that's not to say all of them aren't doing it at some time.

Perhaps one of the three TDR member/dealer techs who know and work on our trucks will think of something and clarify it. In the meantime, if you don't see CELs, codes set, loss of oil or coolant, and it continues to run fine I'd continue using the truck as normal.

 

[EB]

I had that happen to me a number of times and posted about it a number of times. That has been several years ago right after I got my 07 cab and chassis. You just went through a regen, it is nothing to worry about. I had truckers call me and tell me something had gone wrong with my engine. It also happened at idle a few times. White smoke and it doesn't smell very good either but nothing is wrong.

 

[jaird]

Is it a common practice to leave the engine running while fueling? I was told that this was not good for common rail engines but don't remember why.

 

[dquaney]

Is it a common practice to leave the engine running while fueling? I was told that this was not good for common rail engines but don't remember why.

I can't wait to hear the rest of the story on this one. As soon as you remember why please let us know. I am sure I was holding my mouth correctly.

 

[jaird]

I can't wait to hear the rest of the story on this one. As soon as you remember why please let us know. I am sure I was holding my mouth correctly.

I am sorry my post appeared offensive. Wasn't meant to be... just asking for information.

 

[HBarlow]

Dan & EB,

Have your trucks had recent software upgrades?

I took mine to Mike Mullenax in Athens recently and let him install the latest ECM reflash. I don't know exactly what the reflash accomplished but part of it was designed to improve regeneration and allow idling for long periods without sooting up.

Cummins engineers are constantly rewriting the software for our engines to correct minor issues and improve operation so you might want to consider it.

I've never noticed mine smoking at idle but couldn't state with certainty it has not done the same.

jaird: Some owners idle their trucks frequently. I idle mine quite a bit and have never had any ill results. My female German Shepherd spends 24 hours of everyday with me wherever I go including in my truck. I frequently leave the engine running at fast idle with the ac on for her. Early info on the ISB6. 7 engines was to avoid idling but the refined software has apparently made it okay to idle if the owner wishes to. The chassis cabs have the capability for a pto which could require them to idle for hours on jobsites running pto driven equipment.

 

[EB]

Dan & EB,



Have your trucks had recent software upgrades?



Harvey, my truck hasn't had an upgrade since it was new. If you remember, a dealer put a pickup flash (upgrade) on my cab and chassis and totally screwed it up. It (the computer) had to be completely reprogrammed. Nothing has been done since that happened. That was around Feb. or March of 2007. The truck is still running great, I've had no problems. I know there have been a number of flashes come out since then, but the way I feel about it is, if it ain't broke, don't fix it.

 

[jaird]

Harvey,



Is it ok to fuel a common rail truck while the engine is running? When we got our truck, the dealer said that you should not fuel the truck with the engine running but I can't remember why. There were on restrictions on our '90 or '96 nor on any of the road tractors I have driven (many with electnonically controlled engines). Thanks.



Jesse

 

[JGilbert]

How is the fast idle enabled? Is it a box that is purchased? Does the dealer need to enable it through a software flash or somesuch?



Joe

 

[dquaney]

I have not had a reflash on my computer either as I agree with EB, "if it ain't broke don't fix it"

 

[HBarlow]

Dan,

My nature is to be a skeptic of unknown and uncertain ideas. I was also a skeptic about a reflash but discussed it with Mike Mullenax and was comfortable with his explanation. TDR members sag2 and Bob4x4 are also dealer Cummins techs and they recommend having the latest reflashes performed.

I was concerned that Cummins/Dodge engineers would slip reprogramming into my ECM that would reduce power or economy or another trick I wouldn't like. I am confident that didn't happen. The latest reflash was done on my truck and remains comletely invisible and undetectable to me. If it refined the regen process and prevents a future problem I'm happy.