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Seems like there aught to be something coming up in the DIC if that's the case, it's more than happy to incrementally restrict my top speed for every other little imperfection it's super smart little brain detects until I address it...
 

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during the regen the carbon (soot) in the DPF is burned off to an ash. So..... in a properly operating system to me the question is. Is the white "smoke" unburned fuel or just the white ash from the DPF regen process. Under a reasonable highway load I wouldn't expect to see the ash as visible. But stop at a light, not much exhaust flow, ash is still being formed and give it some throttle and what may be coming out is just a pile of ash.
 

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Actually, the carbon (soot) burns off using oxygen released from the exhaust gasses by the DOC (Diesel Oxygen Catalyst). The carbon combines with the oxygen (C + O2 = CO2) to form CO2, which is carbon dioxide, a colorless, odorless gas, which exits the exhaust pipe.

Ash is NOT formed from the burning of the carbon, it is formed in tiny, tiny amounts from the combustion of impurities in the fuel and lubricating oil - that's why trucks with DPFs need low ash oil.

The ash accumulates in the DPF, TRAPPED BY THE FILTER, and eventually clogs it, requiring specialized cleaning.

If I remember the regulations correctly, the EPA requires the DPF to go at least 150,000 miles before needing cleaning.

So, bottom line, the white smoke is NOT ash. It is partially burned fuel from an oxygen starved environment in the exhaust line. Oxygen starvation occurs when accelerating if the 9th injector is sending too much fuel into the exhaust.
 
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