[bjcarls]

OK, in the past 5 months this has happened twice to my wife in fairly similar situations/outcomes.

The car, 2016, 340i, every option + M power/sound kit.

Today she drove to school to get the kids, parked, turned the car off, 10 seconds later turned it back on to keep the AC going. White smoke started to emit from the tailpipe with a high pitch sound (maybe under the hood...faint whistle). It was "definitely white smoke" and it went away while idling after 1 minute. No RPM surge while idling.

She turned the car off (everything normal by then) got the kids, started the car, white smoke again but no noise, she drove away and it stopped. She checked the temp gauge and said it did raise a little on the way home but we only live 3 miles from school so maybe it didn't warm up. It never went above 12 o'clock. My son started to watch the temp gauge to report to me.

It did not throw a warning light this time or when it happened March of this year.

Anyone experience/solve something like this? Of course the car went out of warranty in May... *Edit: I did have the dealer take a look at it before the warranty expired, after the first time and nothing came back, no codes thrown.

I searched and someone had a lose breather hose, spark plug, etc, I'll check the breather hose. I was in the car this AM and had zero issues. No low coolant warnings but I'll check manually when it cools down. No puddles under the car. Edit: I checked and its as clean as can be.

Thanks for your help.

[bimmer456]

Had the same thing happen but dealer could not replicate.

[Wgosma]

white "smoke" from tailpipe....when car is cold moisture condenses in the exhaust system, fire the car up and the exhaust gases heat the moisture = steam, thus the white "smoke". common occurrence for any car with internal combustion engine shortly after startup from cold condition.

[ggrcrash]

Check covering pan at the bottom of the engine, look straight down if you see any white residue dried or any blue colored liquid...probably the coolant inlet hose to the turbo is leaking...maybe an easy fix, less than 300 bucks, or a really expensive one, new turbo...get ready...5k+... exhaust manifold and turbo is one piece...

[teknic90]

Originally Posted by bjcarls

OK, in the past 5 months this has happened twice to my wife in fairly similar situations/outcomes.

The car, 2016, 340i, every option + M power/sound kit.

Today she drove to school to get the kids, parked, turned the car off, 10 seconds later turned it back on to keep the AC going. White smoke started to emit from the tailpipe with a high pitch sound (maybe under the hood...faint whistle). It was "definitely white smoke" and it went away while idling after 1 minute. No RPM surge while idling.

She turned the car off (everything normal by then) got the kids, started the car, white smoke again but no noise, she drove away and it stopped. She checked the temp gauge and said it did raise a little on the way home but we only live 3 miles from school so maybe it didn't warm up. It never went above 12 o'clock. My son started to watch the temp gauge to report to me.

It did not throw a warning light this time or when it happened March of this year.

Anyone experience/solve something like this? Of course the car went out of warranty in May... *Edit: I did have the dealer take a look at it before the warranty expired, after the first time and nothing came back, no codes thrown.

I searched and someone had a lose breather hose, spark plug, etc, I'll check the breather hose. I was in the car this AM and had zero issues. No low coolant warnings but I'll check manually when it cools down. No puddles under the car. Edit: I checked and its as clean as can be.

Thanks for your help.

Did you figure out your issue? Just happened to me and not sure if it is my turbo or what.

[Th3Walrus]

B58 extended idling in hot weather to keep the AC going and white smoke - usually PCV valve built into the valve cover from what I've read on here.