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Smoking, when starting first thing in the morning

I have a 96 vw golf 1.8 auto.

when starting up first thing in morning, there is quite a lot of white smoke. But for the rest of the day there is no problem. Would be grateful for any advice.

This could be two things.

  1. Steam. Water vapor is a byproduct of combustion. Water vapor in the exhaust system condenses in the evening as the exhaust cools. The water then evaporates when you start the engine and the hot exhaust gasses travel through the exhaust system. Voila! A cloud of steam.

Another possibility is a coolant leak into the cylinders. This will also result in a cloud of steam on start-up. Are you losing coolant? This could indicate a head gasket problem.

  1. Oil. If a small amount of oil is leaking past the valve guide seals into the cylinders it burns off at start-up and produces a cloud of light grey smoke.

I agree with McParadise. A couple of additional points.

  1. It doesn’t take much coolant to produce a lot of steam. The coolant level may be dropping slowly, so even if you conclude that it isn’t changing, check it periodically.

  2. On a few cars as they get elderly, the overflow tank and the radiator become decoupled by leaks. Doesn’t seem to harm their driveability. But it will result in the coolant level in the overflow tank remaining constant even if the level in the radiator is dropping. If the cloud of smoke persists it might be a good idea to check the level of coolant in the radiator when the car is cold and see if it is dropping.

  3. A small amount of white smoke is normal on damp/frosty mornings and people’s ideas of large and small vary. Check your neighbors vehicles when they start up and see if the volumes of smoke are comparable.