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White smoke when idles for a period of time

4977 Views 6 Replies 5 Participants Last post by  NoBrand
Blows clouds of white smoke when idles for period of time
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If it is being accompanied with a whine sound from the turbo you might be getting a little bit of oil from the turbo bearing seal leakage. It's not problem. Does it happen more so after you come to a stop? If you look at some drag cars they do that at the end of a run often it's just a little oil burning from the turbo.
Is it cold, if so its condensation my friend
Have a 2010 Mini Cooper S with 55,000 miles and am in Miami, Florida > the weather is definitely not cold > the white smoke only seems to happen when I am idling for any more than normal length of time with the a/c on > I do not have an oil catch can > did the walnut cleaning about 10,000 miles ago > am going to start using 40 wt synthetic oil (which is recommended for hot climates)and add some Seaform > there is evidence of oil on the valve cover and in the valve cover bolt holes > do not notice a pronounced turbo whine > there is no loss of power > have not yet checked plugs > need to determine if I have a failing turbo, a failing valve cover and PCV valve, failing valve stem gaskets > it does not seem to smoke when driving, coming to a stop, or upon startup > I do seem to use a quart of oil every couple of thousand miles > most frustrating and I do not want to start changing parts out > any pointers?
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on cars that do short under 10 miles drives each time used its possible for condensation to build up in exhaust and cat,, also if the air around the car is damp will do same thing, bmw say 1 litre of oil to 800-1000 miles is normal, could do a head gasket sniff tester check for carbon dioxide in the coolant tell tail sign of head gasket or cracked turbo rarely,
or cheaper one
or better one
I wouldn't start changing parts then...
I would start changing some gaskets though namely valve cover gaskets. head gaskets, as well valve stem seal gaskets.
That should clear up the problem.
When I think about my mini cooper I am reminded of a man that owned a ford bronco 2 back in 1992 when they were that old. He said it's a good runner. I just need to run through it with new gaskets.
That's some of what I basically did. Just starts with the valve cover gasket then I worked my way down to the block after getting the head off. Then I saw those pistons looking at me in the face. And I just went ahead and changed the rings.
The relief after doing that gasket job along with the rings and mains and rod journals really brought my mini cooper back to life. At first I stopped seeing Mini Cooper R56's here in the U.S. after I bought the car in 2010; that was around 2017 or so. Did not see a whole lot of them on the road. But here I am in 2021 mini cooper driving like new car.
I told myself that I would comment and try to help here on this forum. Because there was not much information.
Mike1967 has helped out some. But like each person each book about Mini Cooper including myself can only help so much on the topic. It's not well versed like a 350 chevy engine, but it's not like when I bought a brand new alternator for my Mini Cooper back in 2011 that demanded back then you send your alternator in for a new one.
The core fee was outstanding like 450 dollars if you did not.
And information plenty of people downloaded video's over the years on stuff like how to change the timing chain. They never posted another upload after that.
I myself had problems time and time again after the warranty.
One thing I can say, you were right to turn to this forum. The thing that illuminated me about Mini Cooper and this issue was: It the problem as small as the car..................? I would answer Yes! it is even pulling the engine is smaller. The problems are smaller. The more times you see a problem you'll see you can stave it off at a different point in the engine bay.
EXAMPLE: Now you running the type of oil because you have to no problem with that. But the car is modern and has close tolerances inside the engine(not meaning you can't do or not do whatever). And once one learns the oiling system how it comes up to the valve cover and functions in general. Then one understands some of it can be prevented with maintenance. Like the Vanos Solenoid, or the fuel tank pressure valve, or something that is more so simple; as to never really get to the moment your in right now with the white smoke. little modules and leaks and tiny things for a tiny car. But in the end it is cheaper; there just so much involved that ordinarily, or in my experiences I need to spend the money to do it long way, in order to come back the next time and say well I'm just gonna change the Auxiliary water pump this time. Further more I'm gonna buy two auxiliary water pumps so I don't have to wait next time something small like that goes out. or pay extra for shipping. Doing things cheaper like only replacing timing guides if I have the problem with the death rattle symptom. Staving off the bigger problems by choking off the ability for the car to do that. ARP head bolts so I can remove the head and clean out the valves and ports rather than spend 700 on wal nut blasting which won't clean the tops of the pistons which in turn will collect and turn into a suto term of thermite welding or burning right through the pistons if that bed of soot that collected on those piston tops catches fire. In the end that's a fire hazard. Don't get me wrong wal nut blasting is still very good for the car. over the course of 100 thousand miles probably even 150 thousand miles. You won't have to get into the engine very much it's not that type of car. It's not like a mitsubishi evo from the 2000's as far as parts or reliability is concerned. It does have to maintained and have it's intervals honored according to the intervals and they may or may not be in the book. Like oil I would change that every 5000 thousand miles not 10,000 etc...
That's what the problem was with mine as well as Alot I here about. Some of it was just simple maintenance of a modern car. Which is like the 2nd level of regular maintenance. being it a luxury sport car like a mini cooper.
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First, you need to clarify if it is white smoke, or if it has a blueish tint.

White smoke is water, blue smoke is oil.

One of the classic tell tales of valve seals or guides getting worn or tired is if it idles for a while and "puffs" when you drive away, it's an indicator that the seals are probably getting tired or old. Let it idle for 5 minutes or so and have someone "goose" the throttle while you stand behind the car to get a good look at the smoke to see if it's actually white or blue. It's a little hard to tell white or blue looking back from the drivers seat. Also, blue smoke will tend to linger longer than white smoke.

Here's a little blurb from another site that explains it fairly simply:

Cold Engine
One of the most noticeable signs of worn or cracked valve stem seals will be just after a cold engine start. If the vehicle has been sitting for any length of time or even overnight, the top of the head inside the valve cover will be coated with residual oil that was pumped up earlier during running operation. The rubber valve seal has also cooled during non-operation, which causes it to contract and leave a small gap. When the engine first starts up, residual oil gets sucked down through the bad seal and into the combustion chamber. A large cloud of blue-white smoke will be seen exiting the tailpipe just after start-up.
Idle and Stop and Go Driving
Bad valve seals will show themselves during prolonged idling at stop signs or stop lights in congested city conditions. When the vehicle sits at idle for prolonged periods, high levels of vacuum at the intake manifold result because the throttle valve remains closed. The high vacuum attracts oil in the heads to congregate around the valve stems. Upon acceleration, the oil gets sucked past the eroding seal and down through the valve guide, where it burns in the exhaust. Huge clouds of blue-white smoke exit the tailpipe after each acceleration from a stop. The burning smoke will disappear during cruising or highway speed.
Off-Throttle Braking
Evidence of valve seals being compromised will show up during off-throttle braking, especially when descending a steep downgrade where the accelerator pedal remains static. With the creation of high intake manifold vacuum, coupled with the downward slant of the engine, oil collects toward the front of the valve cover over the head. Upon pushing the accelerator after a long coast, burned oil will exit the tailpipe in copious amounts. The engine will continue to burn the oil longer in this case, but it will still be a temporary condition until finally the smoking stops under normal cruise.
Good news is valve seals are a relatively simple fix. Valve cover off, compress/remove valve springs and keepers, replace seals, reassemble. Takes some special tools and specific knowledge though, you generally can't do the job in the driveway with just a set of sockets.

And other than oil eventually fouling the sparks plugs, killing O2 sensors, wiping out the cat, etc, if left too long, the main thing is the embarrassment of a blue puff of smoke everywhere you go and increased oil consumption. It needs to be addressed, but it's not as immediately damaging as something like a blown/failing head gasket.

White smoke problems are dependent on operation conditions. A lot of low speed around town driving tends to build up moisture in the exhaust. Once up to temp (or accelerating) it blows out and creates a white "puff". Same as cold starts or high humidity, it's not unusual to see a little white smoke as the engine comes up to temp.

Continuous white smoke is a different deal. White smoke all the time indicates water is getting into the hot exhaust and being vaporized. Typical causes are a failing head gasket or (gasp) a crack in the head/block that goes into the water jackets. If you see white smoke all the time, you should get it to a shop to test it. they will either do a leak down test or they may just pressurize the coolant reservoir and see if it hold pressure or it leaks down. The car should not be driven for extended periods if you suspect a head gasket leak causing white smoke. Because it's likely failing to the combustion chamber (ie: how the water gets into the exhaust) it can errode the head/block mating surfaces and then you need to resurface them or, in worst case scenario, they need to be replaced.
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