thick white smoke is caused by coolant do to a blown head or intake gasket, or crack in the head or block causing coolant to get burned. Oil smokes blue. but if you just replaced the distributor in a camry which im gonna guess is a 2.2 you HAVE to reset the timing that may be why it runs rough. If it were the has it would smoke black. Now i dont know wut anti-smoke stuff you are talking about but it probably only does more damage then good.