scr warmup

[Mudflap77]

(05-11-2023 )Rawze Wrote:  regen history looks ok to me at a glance.

What do you mean you don't understand?.. Those SCR and DPF canisters cannot function properly if they fall much below about 450-F or so. IT IS ABSOLUTELY NORMAL FOR THE ENGINE TO JUMP BACK AND FOURTH IN OPERATING MODES TO REGULATE THOSE AFTERTREATMENT COMPONENT TEMPS PROPERLY! ... They cannot convert the exhaust gasses .. and therefore it will not pass an EPA inspection unless those cans stay hot all the time.

THAT IS WHAT IT IS DESIGNED TO DO... Keep the temperatures up and within operating range so that they can convert the exh. gases properly.

-= Sounds to me like you are worried about it actually doing its proper job, and your regen history looks like it is doing its thing as well.

If you want it to switch modes less often, then I would suggest you invest in an exhaust wrap to help keep the temps up.

What I don't understand is why it will going into scr warmup at low idle go inactive at 280f you start driving and it will remain inactive. Scr outlet can be up to 400-500 degrees when stopping at a light, engine at idle for 10 seconds or so it goes into scr warmup start driving it will stay in warmup for 30 to 40 minutes with scr outlet temp over 500f.
Get back to the yard 10 seconds at low idle into scr warmup. Let it do its thing until it's inactive and put it on high idle and bring it back to low idle it will go back to scr warmup.
It seems like it goes into scr warmup everytime it spends10sec at low idle regardless of temp.

If it is doing what's its supposed to when it's supposed to, Perhaps its shedding light onto another problem that the symptoms only show up when in scr warm up. That's what I'm trying to figure out here.
That's my main concern is the way it runs while driving in the warmup mode. Over boosting up to 40psi and chaulfing if not careful when shifting while in warmup mode and only in warmup.

[Rawze]

(05-15-2023 )Mudflap77 Wrote:  .... Over boosting up to 40psi and chaulfing if not careful when shifting while in warmup mode and only in warmup.

That is an engine issue .. not an operating mode issue.

Partially clogged or after-garbage EGR cooler, ... maybe partially clogged egr piping, maybe bad (or garbage after-market) egr pressure sensor.. or just maybe.. the program itself does not match the engine ser# or needs an update.

for all anyone knows.. the turbo itself could have been replaced at some point with the wrong model.

Its anyone's guess... however ...

Turbo over-spooling and chuffing is an engine problem.. not an scr issue.
this post should help... http://rawze.com/forums/showthread.php?t...8#pid22458

[Mudflap77]

Thanks Rawze,
That's was I was trying to get figured out.
What has been throwing me off is that it only happens during scr warm up.
Egr cooler is amazingly still original and is clear no blockage, was cleaned out last year when I was having aftertreatment issues, I visually checked it and a the piping a few weeks ago. I'll take a closer look at the sensors that were replaced, I have gotten a aftermarket sensor in cummins packaging before.
Cummins program matches engine serial #. As far as I know there hasn't been any new updates since it was updated last.
Turbo and actuator was replaced last year due to there being a tough spot when moving the ring arm. Will have to look into the turbo model.
Thanks agian Rawze and Jim T