My car is stock and doing this. Mine is happening after the car is up to operating temps (200f or higher) and especially bad after a highway jaunt and when I come to a stop. It seems to evaporate very quickly yet I have a bunch of soot buildup from it on my exhaust and on the rear bumper/trunk area. I know it is from this because there was carbon spots/black spots on those area's after the smoke/condensation came out and was a very big cloud, but it burns off very quickly like condensation would. I can repeat it, time and time again. Just 3/4 or more the car up in 1st or 2nd gear and come to a pretty quick stop and then nudge the gas, tons of it comes out the exhaust (both tailpipes).
I had taken it to the dealer but they said it was just normal water evaporation, but, this has never happened before a couple weeks ago. Temp today was 55 and humidity under 20%, so this SHOULD not happen on a day like today. Has happened in 60 degree temps, happened in 20 degree temps high humidity. No loss of oil based on the Idrive gauge, havent checked coolant but I will and will also check antifreeze but I believe the dealer did all of that as well. I find it hard to believe that this could be normal all of a sudden, stock (except for BMW Performance exhaust so basically stock).
Does anyone have any ideas on this? NO smoke/or anything at all on acceleration, just when I come to a stop after the engine has been going for a while. And it is worst after highway/sustained higher speed driving (65+ mph speeds). Is it possible the cats are putting TOO much water into the emissions? Clogged PCV? Where would I look to see if coolant was getting in? I have NO leaks on my garage floor either.
E92 Space Gray 335i - COBB, BMW Performance Exhaust (stock tips), style 230 rims, LUX H8 AE's