Is white smoke while regenning OK??

[@exportconnections751]

Thank you for the very well put info. Exactly what i was looking for.

[@Armannortheast]

Hello master. I have truck freightliner cascadia dd15. The truck have 715000 miles. I change crankcase breather. It was leaking. But smoke come out only from breather ? Please and advise for me Thanks and advance

[@ENGINESHOPJOE]

Please call me Joe. Master makes me feel like i need to be smarter or cant make a mistake.. Lord knows i have a bunch of engine skeletons in my mistake closet. If the engine is not logging faults for blowby there most likely is not a problem. Lots of white smoke can be from condensation in the oil that is burning out. That is normal. At the mileage your engine is at I would expect some crankcase vapors or blowby. In our fleet engines with 750K miles usually have 21000-25000 hours on them so they will have blowby. *Do an oil sample when you change oil.* If it comes back with no water coolant or fuel in the oil and metals are all normal most likely everything is fine.

[@denistrisic4951]

Ive got a fault code 3375 and 2754 and on my dpf differential pressure history numbers are high 1.3 3.8 4.1 5.6 0.9 and i only put on the truck 100k miles since last time it was cleaned any ideas what to check also with key on engine off my dpf differential pressure reads -0.02inhg

[@ENGINESHOPJOE]

The .02 reading engine off is not a big deal. I see that sometimes. Are the dpf outlet temps high ? if it really is sooting up the outlet temps will be 100-150 degrees F hotter than the dpf inlet temps. 3375 means it is regenning way too frequently. If the .09 came right after the 5.6 I would suspect the dpf sensor has an issue. Cummins did release a TSB on the dpf sensor. some of them were taking in moisture and then reading incorrect values. If everything else seems normal and the outlet temps are 40-70 degrees above the dpf inlet temps then i would try the sensor first.

[@denistrisic4951]

@@ENGINESHOPJOE Hey Joe thank you for your reply it happened to be exhaust gas pressure sensor tube that goes to the manifold the little metal tube but i couldnt tell it was leaking when truck was idling only when under regen

[@denistrisic4951]

@@ENGINESHOPJOE another quick question when servicing injectors what is the best way to drain fuel out of them before pulling them out or no matter what some of it is gonna drop in the hole and if you get it out with turkey baster will it be all right

[@leontayroberson7560]

I have smoke/haze coming off a stop during a passive regen. It’ll clear once I get up to speed but if I come to a stop again and take off, it’ll start smoking again until up to speed. What could be causing this?

[@ENGINESHOPJOE]

There are a number of things that can cause that. It also depends on what engine model and platform you have. But in general if it only occurs during a regen the dpf dosing fuel is not completely combusting. There are many reasons that can happen. I would check the regen history on your engine and make sure it is not trying to passively regen all the time. If this happens when your in town and lots of idling and low speed driving with not much load it could be your aftertreatment temperatures are cooler so the fuel can't ignite. Once you pour some coal to it the heat goes up and now the fuel burns so it appears clear. It typically is not a sign of a looming issue if regen history is normal. There is a feature called aftertreatment stabilization that can be turned on if you idle or are in town more then on the highway. This is only available in the 2013 and newer isx 15 engines.

[@Daniel-z2j2v]

Mine blows out smoke when it starts a regen and I start accelerating then it clears up. Unfortunately I can’t test the doser I have to replace it see if it clears it up. Also I noticed my truck is using more than usual def might replace that doser aswell

[@ENGINESHOPJOE]

See if you can find someone to run the scr system test- That cleans the def system and doser with heat and extreme flow. We had a couple units using excessive def and the injector was fine- the waffel plate in the decomp pipe broke out and was gone. check that before buying an injector for def

[@Daniel-z2j2v]

@@ENGINESHOPJOE I’m going to pull it apart tomorrow but didn’t know about the plate causing excessive def use but I’ll pull the tube off as well. Unfortunately I don’t have anyone with the insight I’d have to take into the shop but replacing parts would probably cost around the same haha. I appreciate your help

[@AB-mg5sx]

I think that’s my issue now, I have a grass burner no stacks and I got the back of my APU, catwalk, air lines, covered in a grey smoke but looks like dust, I wipe it off or if it rains it takes a few days to cover it back up, when my truck starts to regen I will stop and get out and see if it’s coming out of my exhaust, which it has to be, I just had a new ECM put on and my APU serviced, I’m pretty sure it’s my truck and not my APU causing it cause I see the grey smoke in my exhaust pipe, I swipe it with my finger and do not smell fuel or oil, Pete 579, Cummins 2016 Does that sound similar to what your saying in the video?

[@ENGINESHOPJOE]

If its white and it covers hoses etc it could be dried def fluid. If you unit runs def fluid-2010 or newer isx it does, is your def consumption elevated? you should be using about 2 to 3 percent def(can be seen in the trip information pulled from the ecm on the engine)

[@AB-mg5sx]

@@ENGINESHOPJOE I don’t have a computer to connect to it yet, but cummins is going to look at it monday

[@youtubeisawesome2487]

you didnt touch on the fact that if your dosing injector fails the flow test with too much you have to do the reset and recheck.

[@ENGINESHOPJOE]

Yes you are correct that would be the correct action if it failed with too much flow. In my experience if the catalyst and dpf are working properly even if the injector flows too much there is no white smoke- There will be however excessive temps coming out of the catalyst. I have seen dpf inlet over temp faults and that was related to the dpf injector overflowing. The system does learn how much flow over time. We have made repairs and replaced that injector and catalyst element and regenned the unit with out doing the reset and got overtemp faults for dpf inlet temperature. So the correct way to do it is as you mentioned. My main focus in this video was "why the white smoke" as lots of people ask me that in email so I touched on a lot of items but did not go into procedural depth. Thanks