Got an 82 245GLT with m46 in pretty decent shape. Compression is fine. Turbo has some play in it. Here's the trouble:

Sometimes, particularly after the car's been running for awhile and I've driven it 20 miles or more, I'll shut it down for a few minutes and when I go to start it again, I'll get a cloud of blue smoke that'll go away after a few seconds of running. This doesn't happen much, but it HAS happened and did so just the other day while I was at the local Radio Shack.

Once before, I had been driving the car around town, going from one place to another (about an hour's worth of driving time) and I pulled into the McDonalds for some lunch. I was at the drive-thru window and my car started smoking pretty bad. Tons of blue smoke coming out the exhaust pipe. I pulled into a parking place and turned it off. I checked everything but no visible oil leakage. The dipstick was about 1/2 a quart low. I added the oil and then restarted it and there was a bit of blue smoke for about 2 seconds then it stopped. There was about a 10 minute window from when I shut it off to when I was done checking everything and actually restarted it. Oh yeah, I forgot to mention this. Perhaps it's important. When I pulled the dipstick out, the oil on it was smoking and there was slight smoke coming out of the oil dipstick holder. I've never seen this before and I haven't seen it since. This incident occured about 3 weeks ago.

Anybody have any idea what's going on here?

The only time the car burns oil is when the thing smokes. Other then that, I never need to add oil to it. There are no oil spots on my garage floor so it's not leaking anything.

I'm thinking maybe the turbo or the piston rings.

But if it was either, why would the problem be intermittent instead of continous? And, come to think of it, it it was the rings, I would suspect the compression would not have checked out okay and it would smoke all the time, yes?

Any advice would be appreciated.