· COTM Winner
2014 Cruze Diesel, 2007 Cobalt, 1981 Camaro Z28, 2017 Volt
To me, white smoke has always been associated with burning coolant. It may not be, but I'd keep an eye on coolant levels. You usually can smell it in the exhaust, but I'm not sure if one could after the SCR/DPF systems of the diesel.I'd be suspicious of a coolant leak.
Or maybe DEF was being dumped into the SCR.