This morning i went to go crank my '99 4runner. i turned the key and the engine turned over a few times with violent shaking for 2 seconds then it stalled, and blew out a cloud of white smoke from the tailpipe. I tried it again but this time the engine did not respond at all, the starter motor was the only sound, also blowing out more white smoke. I tried it a third time, same thing. It's a daily driver but the truck was sitting for 3 weeks while i was out of town, before that it was fine. I've never seen any smoke ever. It has 6000 miles since the last oil change, i was about to change it. I use full synthetic and change it every 6000 miles. I checked the oil dip stick, it is full. It has 202k miles on the 3.4. I'm in eastern NC so it's not super cold. I use toyota red coolant, changed it 6 months ago along with spark plugs, pcv valve and other general maintenance.

I don't know anything about diagnosing engine problems. Can someone point me in the right direction? Is the engine gone forever or is there hope? Any theories or ideas? I always try to fix my truck when I can but this is above my skill set. Thanks.