No Codes! No Lights!

Okay, so your current engine came out of a T680 with right hand under cab aftertreatment. Appears that yours is same style? Double stacked under cab? They do have different P/N's, but KW and Pete do stack them different. Also, calibrations are specific the the chassis and size of CAC, intake type, exhaust routing etc. Next question is do you have Cummins Insite?

 

Let's us know when you do. Also, when is last time you replaced fuel doser?

 

I would run a fuel doser test and make sure you are getting the correct amount of fuel first and its not plugged. Second if they are saying your turbo speed is off that will cause heat issues in the dpf system since the turbo controls the heat in the system. Whats the regen history of the truck look like temperature wise when it was trying to regen? Regen temperature history tells you alot what the truck is failing to do on its own.

 

Numbers look good, but definitely too frequent regen. Has the fuel doser (injector for regen) been flowed and leak checked? If it's okay, engine is making to much soot. CAC could be the issue. Test it along with boots and piping. If someone could smoke test intake to DPF would be best.

 

Definitely to frequent. Engine is making to much black smoke to say it the easy way. I would run a snap test but you will have to clear the codes when your done. Disconnect the exhaust after the turbo and run the truck. When you hold at wot for about 5 to 10 seconds it should have a small puff of smoke and clear up right away. If it doesnt clear up you have a issue. First check for boost leaks. If no leaks then i would check the turbo. Pull turbo actuator and check arm is moving freely. You will have to recalibrate when you reinstall though. If the turbo is ok then you could have a over fueling issue from the engine

 

One other thing, has SCR been checked for face plugging? I pretty much work on just the MX, but on it I can watch the DPF outlet pressure during regen to see if is plugging. Not sure if you can monitor it with Insite.

 

How many k on that DOC? Looking at that history looks like those temps may be inverted during some of those regens. Definitely do the aft inj flow tests, snap test and I’d price out a DOC if you can watch a regen and see if those temps are inverted for most of the regen.