[zareh94]

I get a excessive white smoke from my tailpipes after warm for hot startups what could it be??

[Jeff@TopGearSolutions]

In a worst case scenario head gasket. Is drivability of the car effected?
Check your coolant level.

[135Pats]

If you have a serious coolant leak/burn it should be obvious. First and foremost, the low coolant warning (duh). Outside of that, the smoke would have a very distinct sweet/syrupy smell, and you’d be able to find trace amounts of coolant on the oil filler cap, and vice versa.

Oil loss/burn on the other hand is a serious pain to track down. N54s can leak the stuff from so many places. Generally speaking, the head gaskets and main+rear seals are pretty robust. A leaking OFHG or VCG could sneak by you, a leaky head gasket would be pretty obvious I’d imagine.

[01bird]

I was having huge clouds of smoke coming from my tailpipes after the car warmed up. I also would have it when slowing down or stopping. It was a light gray color. My Valve Cover Gasket was leaking as was my OFH gasket. Replaced both same issue. After I replaced both primary O2 Sensors and let the car re-learn the smoke is gone. I cannot tell you how frustrated I was trying to figure it out.

[Bimmer-M3]

It could be turbo seal as well.