Isx15 Cm2350 smoke

[Baldmann81]

Hello all.
Wondering if someone could help me with a question on my truck. About once a month it will randomly puff bluish white smoke out of the exhaust for about 3 to 4 seconds. Usually it seems to do it when I am accelerating from a stop. Truck has 260K and has been demandated/tuned by one of the well respected members on here. No change in how it runs when it does it, and this happened before the demandate as well. Anything to be worried about or look for?