1492-1508 is a fairly wide rpm delta. The theoretical maximum allowed is 25 rpm, but if this truck was under warranty I would have recommended their replacement.Had that burner cavity blown out with the air.
When doing injection quantity test engine speed stayed pretty much around 1492-1508 rpm all the time.
injection quantity was going between 8.2 and 9.8.
For the max DPR out temp before we had sys.protection data reset, it was in 1780sF
Also, checking exhaust brake adjustment, I had engine at 980rmp applying the trigger.
The result on injection quantity was 6.5-7.5 before and 15-16.5 after. And you said it needs to be at difference of 12-14
So, I suppose, we'll need to adjust that too.
17xx degrees is absolutely scorching hot. The ceramic the DPF is made of melts around 1485 or something. 1700 degrees is hot enough to damage the Scr.
Since I'm troubleshooting this remotely, take this with a grain of salt: replace the injectors and DPF. Look at the DPF inlet temp. If around 1300, remove and clean the CAC, and inspect the turbo for excessive shaft wear. Reset the exhaust brake. Set soot amount to 2.2, start a regen, go to engine diagnostic menu , data monitor NOx sensor voltages, def consumption. Outlet voltage should be much lower than inlet when def is being injected. Neither voltage should oscillate. Check P/n of NOx sensors. The latest, best ones end in E0451. If you see oscillation and they're older sensors, replace them both.
My concern at this point is the Scr could have been damaged by that temp. Replacing that would raise the cost another 30%.
Adjust the valves when the injectors are replaced. No one does this on time, if ever.
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