I have a Low Mileage 1991 Porsche 965 (Turbo). Plenty of Oil Pressure at normal Operating Temperature and performs brilliantly. The car has been kept in my garage unused (on the road) for around two years. I start up the car regularly to keep the Oil Circulating and stop the Oil Seals from drying out. I started the car up today and masses of white smoke was being pumped out of the Exhaust. I let the car run up to Operating Temperature as normal but the thick white smoke was still being pumped out. l calmed the neighbours down and assured them there wasn't a fire - kind of them to ask. I shut the engine down and made a coffee while the white smoke cleared. After 20 minutes or so, l started to car up again and,,,,,,,,,,,,,NO MORE WHITE SMOKE - Hallelujah !!! What was going on ???