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Smoke from the exhaust

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1.6K views 6 replies 4 participants last post by  R1916V  
#1 · (Edited)
Hi

The car is '18 T3 1.5. 36800 miles. Is this amount of smoke normal? It has been raining and it's 11°C outside. It was after around 8 minutes of driving. Same happened today in the morning but after 40 minutes drive it wasn't smoking. I don't remember my old c30 spewing this much smoke. Or is it just condensation and I am paranoid? The smoke disappears when pressing accelerator.
Thanks

 
#2 ·
Looks like normal condensation to me.
 
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#4 ·
Hi Again,

I kept observing it since then and it doesn't look good to me but I am not an expert. It's currently 18°C outside, hasn't been raining and I can still see it (much less though). Also I've polished the exhaust tips this Saturday and bottoms are already covered in black soot :(
 
#7 ·
White smoke from the exhaust can be due to two reasons - burning of the coolant or simply water condensation from the burned gasoline.
For the first reason - it is not good, so monitor and check the coolant level regularly. If it stays at the same level, everything is fine.
If it's just water condensation - don't worry. It is normal in cool weather to see this vapor. But if you drive short distances regularly, the last muffler can't get hot enough to evaporate the water and that water stays there. For this reason I always drill a small hole (3-4mm) at the bottom of the last muffler to allow the water to drain freely. This trick also extends the life of the final muffler. On another gasoline car, I drilled the hole after years of using the car only for city driving and in the moment I punctured the hole, half a liter of water leaked out.

Just to add that if the smoke is not white, the reason is different. Bluish smoke if the engine is burning oil. Black smoke from a gasoline engine is unburnt fuel.