SAAB 9-3 2-0 TURBO 54 PLATE SMOKING?

MY SAAB WAS DRIVING FINE JUST THE ODD LITTLE BIT OF SMOKE WHEN WARM DECIDED TO CHANGE OIL/FILTER AND NEW COOLANT.PUT MOBILE 1 15W/50 MOTORSPORT OIL IN AND NOW IT IS SMOKING.IT STARTS AND RUNS FINE NO OIL OR WATER USE AND TURBO BOOSTS AS IT SHOULD.THE SMOKE APPEARS AFTER ABOUT 2 MINUTES WHEN STARTING FROM COLD AND AS ENGINE TEMP RISES GETS WORSE WITH PLUMES OF WHITE DENSE SMOKES COMING OUT OF EXHAUST UNTIL IT REACHES WORKING TEMP GAUGE HALF WAY AND THEN SMOKE STOPS JUST THE ODD PUFF EVERY NOW AND THEN.THE WHITE DENSE SMOKE SMELLS LIKE OIL BURNING.HAVE NOTICED THAT MY ENGINE MANAGEMENT LIGHT IS NOW ON BUT STILL DRIVES PERFECT.