White exhaust smoke upon start up?

I was going to the supermarket this evening and started up the car as always by making sure the oil level was fine etc, and upon firing the engine tons of white smoke came out in one big burst. I switched off the engine after maybe 5 seconds (nothing sounded unusual, and the RPMs were as normal) and could smell the exhaust smelling exactly as, erh, exhaust and nothing unusual except for that is was white (like in not blue or grey) in the direction of water vapour like in appearance (only it was not). So, I started it up again to see where exactly the smoke came from, and was told (someone was looking for me) that there was a little more from the left pipe (when looking in the car's direction from behind) and then it disappeared. Started to drive and only a tiny white smoke came out but nothing after I'd say 2 min. Parked the car at the supermarket, was nervous as hell, came back after 30 min, fired the car up again, and no smoke this time. It started without any problems no error indications, or unusual sounds and everything was back to "normal". Came back home and looked at the floor where the car is parked, and there was no indications of oil or water dripping. Opened the engine hood and could not see or smell anything unusual other than (call me crazy if you will) that lovely Porsche engine smell, that only Porsche has... I drive the car about once a week and it stands still for a min of 5 days in a row (or at least for long enough for the wireless locking system to switch off). What could have caused this and is this something to worry about or is this something that happens once in a while? Is it some self cleaning thing?

I have an 03 Carrera. My car will do this on occasion as well. The longer it sits the more it will emit white smoke.

Thanks brianpizzuti ... brings my heart to rest

There are a ton of threads on this. I would recommend doing a search and reading some of the threads which have a ton of helpful tips. One possible outcome is that nothing is wrong and that you have nothing to worry about. That's probably the most likely outcome. Another is that the AOS is starting to fail. With the engine running, remove the oil filler cap and see if the engine stalls or runs ragged. Is it difficult/impossible to remove the cap in the first place? Those are signs of something you need to look into. Etc. etc. etc.

What's "a ton"? Enough to make a car-sized cloud, or enough to shut down the interstate? An occasional big puff is common and probably nothing. Closing down the freeway with your own smokescreen is definitely something different and worthy of repair.

Yeah ok, a ton was maybe a bit exagerated, but it just felt like there was more than it probably was as I went into a state of "panics". Yes about half a car size I'd say... Btw what's an AOS? And thanks for taking your time with your input. Highly apreciated as always...

The AOS is Porsche's $200 solution to a $1 problem... http://www.pelicanparts.com/techarti..._Separator.htm

I have had that same thing every once in a while. I tend to keep my oil level around half or just below half and it pretty much eliminated this. I find when it is on the upper half closer to full (max) level, is when I see a little smoke on start up. Something about the oil seeping through the cylinders and it burns through the exhaust, especially when full and your riding the car hard and fast around corners. Last time I unscrewed the oil filter canister carefully and just emptied what was in there (1 cup maybe) and that was enough to stop the smoke. I havent seen smoke on start up since....maybe once or twice months ago.

A small cloud of white smoke is normal when first starting your car up if you turned it off while still cold- it's just a tiny bit of oil that seeped past the piston rings the last time you turned it off, and nothing to worry about. It's usually only noticible when you turn the engine off cold, because that's when the seal between the pistons and block is the loosest (heat expansion and all). It's easily reproducible- wait until you car car cools down, turn it on, and turn it right back off. Come back a couple hours later and start it up, and you'll get a puff of smoke every time. That *should* be it, though- if more smoke keeps coming out, or if it smokes on startup even when put away hot... something else is amiss. Chances are that you'll get a CEL to track it down if that happens, though.

Thanks for all your extremely detailed answers and differnt views on the issue. I'm learning as I move along so this is very valuable info... Will take my beloved car out for a spin today and see what happens when I fire her up. Thanks again for taking your time answering a novice :-)

OK, started the car up again this morning, and to begin with (the first few seconds) it all seemed fine, but then the white smoke came out again but much lmuch ess than yesterday. Let the engine run for a little and there was no vacuum holding the oil cap back so stopped the engine again. Instead of speculating in this and that, I have booked an appointment with Porsche in Bern and will drive it up on next Saturday and just leave the car in the basement until then. The drive is less than 20 min away (36 km) and it seem like it's only at startup it's not as expected. Will also get the indicator module replaced while they have it so need to work overtime again this month ;-) I will get back with their verdict and share for the record. Cheerio

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That's normal.

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I gather you mean that the AOS is ok then or that the extra white exhaust came as expected?

Being able to remove the oil filler cap is normal. Not being able to is a sign of a problem. I will repeat my advice from my first post in this thread, do a search for white smoke on start up in this forum. You will find a ton of helpful posts from people who know a lot more than I do about these cars. You can then decide what to do based on your circumstances.

Oil level is to high. White smoke is the sign. I'll await your verdict from the dealership.

Posts like yours show up every year at this time when the weather starts to cool and water vapor becomes more common at cold engine start. Did the cloud dissipate quickly or linger/hold together? If the former the cloud was water vapor (mostly) with a small oil vapor component and probably normal. Even if the cloud lingered as would be the case if it were almost all oil vapor this can be normal. The oil comes not from past/around the rings but from a lousy, err inadequate AOS that let some oil vapor through to the intake the last time the engine was run. The vapor contacts the intake walls and becomes a thin coating of oil. Over time this then drains down into one or more combustion chambers where it gets burned the next time the engine is started and the cloud of smoke you see comes from this. Provided the cloud of smoke is brief and the engine exhibits no untoward behavior and the CEL remains dark the cloud is nothing to worry about. What can contribute to the propensity of the engine to smoke like this is short trips, over filled oil, or oil that is past it change by date. Now short trips mean the oil doesn't get hot and thus builds up a larger than normal load of unburned fuel and water. This does several things. It increases the volume of oil in the engine; it thins the oil and increases its propensity to foam and create more oil vapor when the engine is running which further overloads an already inadequate AOS (air/oil separator); and it accelerates the formation of acidic compounds in the oil. For the above reasons the oil should be changed more often if short trips are the norm. Oh, I note you park the car in a basement. Generally a basement can have a rather steep incline which can momentarily increase the oil vapor content of the oil in the crankcase as the oil in one head, under one camshaft cover runs to the end of the cover away from the oil scavenge pump and this results in the oil that accumulates under the camshaft cover getting whipped into a froth from the camshafts spinning and then when the car is on level ground the build up of oil is removed by the scavenge pump but this sudden rush of oil through the scavenge pump results in the creation of even more oil vapor which some then ends up on the intake walls. The engine is shut off very soon after and this vapor that has gathered of course drains into one or more combustion chambers and well, you know the rest. Nothing you can do about the basement. You can let the engine idle a while (~30 seconds) but there is no real guarantee this will help, be enough time for the oil on the intake walls to run down and be burned in a hot engine. As the engine runs the wall are cool and the oil not so anxious to flow. Once the engine is shut off though the intake warms up from the heat from the engine below it and this warms the oil on the intake walls and of course it will then flow down and into the engine. 'bout all I can advise is you can certainly have a Bern Porsche tech check out the car/engine. Be sure the oil level is ok. With the engine fully up to temperature the oil level can be at the max line but it should not be over this. Consider changing the oil more often to cut down on the amount of thinning of the oil that occurs as unburned fuel and water accumulate from the short trips.

+1 on AOS. I'll bet that's your issue.

Thanks Macster for the very detailed explination.

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Macster, I think you're wrong about this. If your theory is true, you'd see the same puff of smoke every time you turn the car off- but it doesn't happen to our cars when parked hot, only when parked cold. And it happens EVERY time when parked cold, not just in certain weather. CW is that it's pooled oil seeping past cold pistons.

So I have taken the car out a few times after the first cloud burst and after I spoke to my local Porsche garage (who gave me the green light to do so based on my observations). There is still a little white smoke coming out the exhaust when I start the car, but nothing close to what I saw the first time. It seems like it doesn't matter how long (or short) it has to be turned off for the smoke to re-appear as I took it for a wash after a 2 hour drive, and 20 min of standing still was enough for smoke to reappear. Anyway, service booked for the 7th of November so cross my fingers it will not be anything major. Foot note: I called the official Porsche Zentrum Bern last week to hear if they could take the car in, but they had massive waiting list of over 2 weeks

a little rhyme from po smoke....sometimes cold sometimes hot.....sometimes alot sometimes not. disreguard the fairytales about parking it on a up/down/left/right tilt or idling for a minute. mine has /is been doing it from 09 when i bought it new. it is embarrassing at times and i stopped trying to tell people is normal. mine even did it the same day after a dealer oil change,at times it looks like a smoke grenade for a LZ. it has just over 20k on it now and only babied it for break in

^^^^ you really think that's normal?

New Pope? Ah, couldn't resist....as always Mac has a great explanation and we all should be aware that these cars seem to develop personalities to a higher degree than other vehicles. I suspect we also pay more attention to them, and I agree that if the issue is intermittent and brief, don't worry....but for peace of mind, you can always shell out a few bucks and have it looked at.

Mine does it occasionally, especially if I am running it hard and then turn the engine off. Upon startup it'll happen. Then at the track it almost always does it. It'll happen less if you keep the oil level low but it's still somewhat embarrassing. Don't feel that bad though. I was on a mountain run with a brand new GT3 a couple of years ago. We went out to lunch and when we came back and he turned his car on there was a huge plume of smoke coming out of his car for about 5 seconds. Then it cleared up and that was the end of it. But imagine if you didn't know any better and you thought your $130k car just bit the dust?