Exhaust smoke one time, but then not again

[leftfield6]

Got my 83 on the road today, and have a little smoking problem. Here's what I'm getting. Started the car up this morning and headed out for a test drive. Getting out of my subdivision means going through two stop signs before getting to the subdivision exit.

Now that you have the lay of the land, here's the chronology. Leaving my driveway, up through gears to 3rd, no smoke. Leaving first and second stop lights, up to 3rd or 4th, no smoke. Exiting subdivision, I get exhaust smoke in first gear, second, and into third and fourth. By this time I'm doing 45 or 50 so any smoke is diluted enough that I can't see it if it is there. At the next stop light, off going up through the gears, no smoke. As a matter of fact no smoke the rest of the day as I used the car to run multiple errands.

I know from past experience though, it will do the same thing tomorrow. Not at the same exact time, but at some point early in my forst drive, I will have a smokey run up through the gears.

Any ideas? It looked more whitish than blue or black.

[So Cal Mark]

smoke from the exhaust pipe or under the hood?

[leftfield6]

Exhaust pipe. No external oil leaks on engine.

[jctucker]

Total shot in the dark here. White-ish could be coolant. Is it possible as the engine travels thru its heat cycle a little coolant is escaping into the head gasket or something?? Again, just a thought. I've never seen a car that only had a head gasket leak in a small part of the heat range.

[bradartigue]

You may have a leaking valve stem seal. When they are old and brittle they develop cracks and/or fail to adhere to the valve stem when cold. When you first drive the car oil isn't moving around so well (it's cold too), then it gets thin and under pressure and goes down the valve stem and burns. At the same time that old seal is heating up and getting soft, eventually it does seal against the stem and the oil stops running into the combustion chamber.

It takes an extremely small amount of oil to produce a good bit of smoke, so I wouldn't worry too much if it goes away once the car is warmed up.