replied 1 year ago.
Thanks for answering my questions. Actually I did not get much help from your answer because the way all this system is set up, it was more of a frustration and waste of the time,for me, than a help. But at least I know now, this way of solving problems in emergency situation is not working and it is waste of time.
The way you put your answer was confusing and unclear. If you assume you are talking to a mechanic, than I think it is a shame to charge fifty bucks just for code explanation. If you are talking to some one with out enough mechanical knowledge, so how do you think they will figure out, how to check components, where they are, what they look like?
No offense, I just expressing my opinion, I did not score your answer, do not want to ruin your rating, that is not my intention.
It might be just me not handling well the entire situation.
Here is what I did. I replaced urea dozing valve. The new one has nice foggy spraying pattern. Put new upstream nox sensor, because of corrosion I messed up the tread a little bit when I removed for inspection. Did regeneration for more than on hour. Than I stopped. It would never stop on its own. What it time frame for the parked regent anyway?
Codes are staying with no change.
I cleaned that sensor, do not know the name, but it is in egr system. Took out 7th injector, to check operations, look as it not spraying right, but it is hard to see it if it is not moved away from the exhaust because you can not see due to smoke which is coming from burning fuel. Measured temperatures. By injector I think was around 400°, lowest temp sensor on dpf housing was up to 372°, in front of catalyst was 440° and same right after catalyst, opposite side pipe from down stream nox sensor.
I replaced 7th injector, and temp readings got a bit better. Between turbo and 7th injector goes 430°-452°, after the injector 462 and goes to 473°, by middle temp sensor on dpf housing 439°,lowest temp sensor, on dpf housing 471°and goes up to512°, front of catalyst 570° goes to 604°, after catalyst 460°-520°.
I do not know what these temperatures suppose to be, but I think they are unacceptable low for parked regeneration condition.
Anyway, after about 40-50 minutes, finally, it got done, rpm come back to idle, yellow ''check'' light went off, but aftertreatment light was on and the code #5349. Other two codes were gone, and truck finally was out of derate mode.
After I restarted truck later on, aftertreatment light went off, but active code is still there. No lights on.
By the time engine was exiting regeneration mode, there was very loud whistling noise. I took the truck for the test drive. That noise is present most of the time above 1100 rpm, as boost increases, the noise gets louder. Some times it stops, than comes back. I had this noise earlier too. But it was mostly quiet, just it comes sometimes.
I believe that is egr valve is not closing properly all the time. And that is why engine is not able to race temperature sufficiently during regeneration because mixture is being diluted by exhaust gases which should not be present during this process, my opinion.
What do you think about all this? What these temperatures suppose to be? Can egr valve make this kind of noise? Which temp sensor is ecm reading when is showing exhaust temp on driver display? How is inoperable egr valve affecting fuel mileage on diesel engines?
I would appreciate your impute on all this. Thank you again,