ISX CM 871 intermittent smoke

[deepster77]

i have an isx cm871 in my 2009 peterbilt. i have intermittent turbo " cough" and an occasional white smoke smelling like fuel. it seems to be overfueling occasionally. i have replaced 3 turbos, all timing and metering selenoids, injectors, complete genuine cummins overhaul, head rebuilt, imapsensor, exhaust back pressure sensor, and delta p sensor. dpf has been cleaned and baked. had it dyno'd at kenworth nad they said all is good, had a mechanic data log it on a trip and send results to cummins and they said its ok. but i know that this engine shouldnt smoke and i know what over fueling smells like. HELP!!!
the ecm did need 7 updates and those were done earlier this week. no codes on the dash.
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