White Smoke out of Exhaust! Help
 

So i'm having an issue with my 2011 mini s and was wondering if i can get some info from you all... here it goes.

Check engine light was coming off and on for a couple weeks. I took it to my local mechanic he said the O2 sensor was kicking it off and on. He reset it, ever since i have had two other mechanics look at it and nothing. The check engine light has not come on and no one can find the O2 sensor problem in the diagnostics. Since then (or it could have been longer) I have had white smoke come out of the exhaust, mainly when i'm idling for a few and take off. Big cloud of white smoke. It is burning some oil quicker than usual. My oil light came on 2K miles before i was supposed to get it changed. There is about 120K miles on it.

I had another mechanic look into it today and said it drives fine but he did see white smoke, suggested some stuff he could do the next oil change. Could this the turbo going bad? Bad piston rings? Valve seal?
Any help would be greatly appreciated. Thanks!

Oh also, i checked the coolant. The tank was full.

I have an R53, just reading your post. Usually White smoke is coolant, blue smoke is oil.

Ever figured it out? I have the same car and same thing, idle for a bit then I take off and there's a white cloud out the back. I did have a coolant leak but I think I fixed it a couple weeks ago. I don't know how long old spilled coolant would evaporate back there for.

It may be oil burning. Oil burning can look like a water leak, because it is very light colored, almost white, but it lingers in the air, unlike a water leak.
You may need a new PCV valve, which is incorporated in the head cover, That means new head cover.

I actually just changed to a new valve cover a couple weeks ago. Is that the same thing? There was oil in some spark plug tubes and stuff so maybe i’m just burning off the lingering oil that was left over from when it was leaking?

Yes, head cover and valve cover are the same thing, MINI calls it a head cover.
Try taking it on a long drive and see if it goes away.

I had white smoke coming from my R56 JCW after they replaced my thermostat housing because of a coolant leak. After a week or two of driving, the smoke went away.

I had the same situation, I changed the thermostat housing and the white smoke went away. I had a theory associated with the coolant turbo lines. If there's a leak in the system the pressure is not right and because of that there's no enough pressure/coolant to get to the turbo lines. That's why when idle (low volume) the turbo overheat or whatever====>white smoke.

I am experiencing the same problem with white smoke constantly after new valve cover and engine oil + filter. The smoke appear only after engine reaching operating temperature (108c).

Any help would be much appreciated.

Thanks.

What brand valve cover? Just wondering if it could be defective?

Original valve cover from BMW

I have the same issue on my 2011 JCW.
 

Did we ever figure what is causing this? Im not leaking coolant and everything is fine with the oil. I also have good compression. Must be the thermostat housing allowing coolant somewhere it's not suppose to be.

I have not done anything after the valve cover change, the white smoke condition still persist.

My analysis as below
1. no coolant leak as the reservoir is clean and clear of oil
2. no error code
3. no lost of power
4. oil lost yes.

My guess is valve seal. I have yet to get it fix.

One more thing.
 

Thanks for the post. One more thing....with the engine running....if I remove the oil fill cap....there is a decent amount of smoke coming out. Can you check if the same happens on your car? To me valve seals make since. I only have 52,000 on my JCW....always well maintained. Can you check for smoke coming from your oil fill cap with the car running? Any idea how much it costs for valve seal replacement? I know it can be done without removing the head.

Yes, my does have decent amount of smoke coming out from the valve cover too. My current mileage is 154000 km.

The other thing that u ca check cylinder compression test to rule out piston rings.

Also can check the intake hose to turbo if excessive oil - this could be turbo oil leak.

Actually for my case, i have yet to determine if it is valve seal or turbo seal leak or piston rings. I have yet to find time to perform a compression test.

Back from the stealership
 

I had very low expectations taking my JCW int to a dealer (have never had good luck with them). Their advice: change the valve cover if not that then change valve stem seals. Ok. But that doesnt explain sweet smelling white smoke from the exhaust.
compression test was all good, not leaking any fluids, no codes and no loss of power. Anyway, I have two spare valve covers so I will give it a shot.