Blowing smoke when cold?

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Apr 28, 2015
Reunion Island
Hi, I noticed something curious on my wife’s car (Koleos in sig): Every morning, she starts the car (flat surface), put the vehicle in gear (6 speed AT, torque converter) and climbs the 100 meters, 35 degrees uphill that leads to the road. About 20 meters after the beginning, the tail pipe starts to blow a fair amount of something opaque, can’t tell if it’s blue or gray, but it’s not heavy (it dissipates quickly). Of course, after climbing, it stops to blow. What is this smoke? When I saw my brother in law climb with my Yaris, I noticed some smoke too but it smelled like ultra rich cold exhaust fumes. Ambient temp: 70-80 For
Wait at the spot where the smoke appears. I think you'll be able to figure it out. Like BrocLuno posted, it's probably water vapor.
If it stops, that's gonna be harmless smoke of some sort. Cold will allow smoke to hang around for quite some time, depending. Water can and will drip out a tailpipe due to condensation. Hot exhaust, cold air.
Unless you are losing coolant or oil and there isn't a sweet smell to the exhaust, I wouldn't worry about it. Life is good.
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Originally Posted By: Superflan
Concerned by the fact that it happens when doing the uphill cold and engine load, might it be oil?
Uphill incline will cause condensation to run down the pipe, hit a hot area of the exhaust, steam up. My truck does that alot. Doesn't burn a drop of oil. You would know if oil was a possibility, check the oil 2-3k after an oil change. Is it down significantly? Then maybe its what you see. If its blueish.
Probably water vapor or unburnt fuel (rich open loop cold engine) When you burn fuel it creates water. If it doesnt do it fully warm it is likely nothing to worry about.
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