Medium and Heavy Trucks
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Hello! My name is ***** ***** I will be happy to assist you with this question. In my experience it is near impossible to determine if a DOC needs to be replaced based on a fault code alone. Without the ability to view the vehicle and graph the temperatures it is also hard to say. However, I do highly recommend removing the DOC and checking to verify if it is face plugged, a DOC must be replaced per Cummins specifications if the catalyst is face plugged. (there will be a layer of black or gray soot covering the entire face of the DOC if it is face plugged. Shine a flashlight thru the rear of the catalyst and if you can not see light out of the opposite end, it is bad) Also, if you remove the DOC and it is breached (there is soot stains on both sides of the filter) it is bad. I have seen fault code 4214 present in systems that needed to be cleaned as well as replaced. The life cycle of these filters is highly dependent upon your idle times, regen cycles and general age. I have seen filters go a million miles before having problems and also about 200,000. I understand that these filters are very expensive, so it is best to see the filter itself and ensure it is in fact faulty prior to replacement. If you were to take the unit into a Cummins facility and the filter did in fact need to be changed, a technician would need to connect via INSIGHT and perform the aftertreatment reset procedure after installation. If you have INSIGHT i would be happy to assist you in doing that yourself ;) If you are going to be removing the filter yourself, ensure that the diff tubes are removed, inspected and blown out with compressed air to ensure they are not blocked. If the catalyst is in fact face plugged I also recommend having the DPF cleaned as they work off of each other. I hope that I have been able to answer your question. If I can be of further assistance please let me know. Thank you!
Hi there, just wanted to check in and see if you have resolved your question? If I can be of assistance please let me know. Thank you!