Hello.

This morning I had a vapor coming from under the hood but no check control messages, odor or mess. Here are the details:

It was around 35 degrees this morning. No problems starting. I drive a short distance on surface roads before hitting the highway (55/65 mph) for 5-10 minutes. There is a light at the bottom of the exit ramp which is when I saw the vapor. There was nothing at the next light or when I pulled into the parking lot 5 minutes after exiting the highway. When I parked, I opened the hood and there was no moisture or signs of extreme heat. The engine looked quite clean.

I have put 6k on the car and this has only happened one other time following the same scenario as above. Is this normal vehicle function or are there tests I can do for further analysis? Thank you.

 

Possible culprit found.

I checked the coolant level and the fluid is up to the top which is above the fill line displayed. Perhaps the cold weather is causing some of the extra fluid to vaporise? In any case, I plan to remove some of the fluid this evening to get to the correct level.

 

To better help you in the future please note MY and model

 

Good point. So wrapped up in the details I forgot the obvious. The car is a 2007 530i manual with 45k. Thanks for the classy reminder! Some forums would have included some additional descriptions regarding my lack of intelligence

 

I had a similar experience when I pulled into the parking garage at work with my '05 545i after a 20 minute drive and stopped - weather conditions were similar to what you described and vapor/smoke came out of the kidneys. I was concerned as well, but searched the forums for info and remember seeing a thread somewhere that explained it may have been caused by some condensation underhood that upon stopping travels forward and hits some hot radiator parts in the kidney area, thus producing the smoke/vapor you saw. Frankly I'd be very surprised if it was caused by your cooling system in any way since it's pressurized and if any coolant really escaped you'd have a major problem on your hands.

That was almost two years ago, never had it reoccur since then and whenever I had the car in for service no abnormalities were found. Bottom line - I wouldn't worry about it. Hope this helps!

 

Thanks for the tip obacht545. I think you are correct as the steam did come out of the kidneys. A rather odd phenomenon but its great to know there is a logical explanation.

 

i also noticed the same, and it turned out i needed valve cover gaskets (i think thats what it was).. oil was accumulating and then burning causing the white smoke. could be that or something else. good luck