Toyota RAV4 White Smoke

When I Get Onto Interstate And Punch On The Gas To Go, A Big Puff Of Blue Ish White Smoke Comes From Back Of Rav 4 Even If I Slow Down...

My Toyota Puts Out A Puff Of White Smoke From The Exhaust When Started. It Only Does If The Car Has Sat Idle For A Few Hours (ie Overnight...

97, Rav4, 119+, Puff Of White Smoke Every Time Car Is Started, Not At Any Other Time Car Is Moving Or At A Stop Light. What Should I Check...