Sudden Smoking

[jjrowe]

I think I know what my issue is but I wanted to get some additional feedback. My 1976 911S just started smoking last week. I noticed an occasional cloud twice last week and immediately pulled over only to find no smoke or evidence of smoke while the car was idling. The car doesn't smoke at startup either. Yesterday I noticed more smoke on the way to work, mostly when I let off the accelerator. On the way home yesterday much more smoke, by the time I got home I was leaving a huge cloud of smoke. I pulled the plugs and number 2 looks wet, the rest look good. So it looks like a bad valve guide seal on number 2, probably exhaust which is leaking lots of oil into my headers causing all the smoke. Three questions:

1. Anything else that could be causing oil to leak into the exhaust?
2. Is a sudden failure common?
3. Based on my searching it always seems to be valve guides on cylinder #2 that fail first, anyone know why?

Thanks,
Jesse