Not always as slam dunk as white smoke means coolant. If you still have cats, you can get grey-white smoke from unburned fuel. What does it smell like? Sweetish? that's coolant. Look inside your overflow, if you're down on coolant that could indicate or its full of milkshake spooge, that's oil getting into the cooling system. Pop the plugs out and take a look. heavy crusty white or reddish coolant deposits is a giveaway. If it hasn't been happening long you might find one plug cleaner than the rest type of thing.
A compression test is in your future...maybe when you pull the plugs you can do that
2014 Premium GT, SGM, Brembo, Auto, Tech, Comfort, etc. GT500s, Steeda UCA, VMP auto N/A tune. 100 shot nitrous on BBR tune. Best e/t 11.42 at 120.64
2012 Premium GT, Candy Red, Brembo package, 3.73, MT82, Comfort, Tech, et al. Procal tune, Roush UCA, UMI poly LCA, GT500s, Steeda red bracket, Hoosier 28x10x16 bias drags. Best e/t 11.91 at 115.23 RIP