white smoke on cold start
10-01-2014, 02:23 PM
#32
Race Director
However, if I didn't make it clear before let me do so now and that is not every short trip will result in the engine smoking upon the next cold start.
Based on my experience the more miles the oil has upon it the more likely the engine will smoke upon a cold start following a short trip but even with 5K miles on the oil not every short trip will have the engine smoking at the next cold start.
As long as the smoking is brief, essentially it stops as soon as it starts, is not accompanied by a CEL or any untoward engine behavior (lumpy idle, hunting idle, what have you), the smoking is nothing to worry about.
This doesn't mean the AOS, for instance, won't at some point fail but this brief smoking is not a reliable sign of any pending AOS trouble. You still have to be aware the AOS can fail at some point but its failure is almost always accompanied by clear symptoms that something is amiss and needs attention.
Last but not least, I do not know if this has been covered, so I do it now, you can always have the car checked by a professional tech. If you know how to reproduce the behavior reliably tell him and let him experience the symptoms as you do and listen to what he has to say.
10-01-2014, 02:33 PM
#33
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Hi Macster, it is in the shop today for oil change, I have explained what happened to them,
we change the oil every 3000 miles max, we changed when we put it up. the day we take it out in April, again in July and now before we put it up again, I am very **** about keeping fresh oil in it..lol
Thanks for your help, but when she drives it she has always let it run for 10 minutes, then drives the mile to work and it sits flat in parking lot for 9 hours, never had it happen, but it was very cold that morning and warm in the afternoon is the only difference I can figure out. this is our 3rd summer, we have averaged 7,000 miles per year.
we change the oil every 3000 miles max, we changed when we put it up. the day we take it out in April, again in July and now before we put it up again, I am very **** about keeping fresh oil in it..lol
Thanks for your help, but when she drives it she has always let it run for 10 minutes, then drives the mile to work and it sits flat in parking lot for 9 hours, never had it happen, but it was very cold that morning and warm in the afternoon is the only difference I can figure out. this is our 3rd summer, we have averaged 7,000 miles per year.
Last edited by Maclen; 10-01-2014 at 02:35 PM. Reason: add info
10-01-2014, 02:33 PM
#34
Drifting
Macster, your theory about oil vapors through the AOS does not mesh with observations; it makes no sense that oil vapors from a cold engine would make it through the AOS and smoke the next startup while oil vapors from a hot engine wouldn't. Set up an experiment to test your theory; I did; that's how I know the smoke is only associated with parking the car cold. Oil leaking past cold rings is the only plausible source of that oil I've heard.
AOS simply failing from old age is plausible, but your theory of old oil contributing doesn't fit the anecdotal evidence which is a surprisingly large % of AOS failures are reported right after people have their oil changed or top off their oil. Remember- this isn't only subjected to oil vapor, but liquid oil as well. Lot of signs point to overfilling the oil as a major contributing factor. Regarding very frequent oil changes, it's well documented in industry that excessive maintenance can actually CAUSE failures just because it increases the risk of human error. Nothing in any of the oil analysis I've had Blackstone do shows my oil any less able to lubricate my engine at 8k or 10k than at 3k. At best, you're wasting money; at worst, you're increasing your risk of human error causing problems 3 or 4-fold.
Low AOS failures at high alt is interesting, too; lower ambient air pressures would lead to less of a pressure differential and a lower volume of air through the AOS. It should lead to higher % levels of oil vapor in the air (vapor pressure), but lower volumes of oil mist and other liquid oil, due to the reduced airflow pulling less oil up.
AOS simply failing from old age is plausible, but your theory of old oil contributing doesn't fit the anecdotal evidence which is a surprisingly large % of AOS failures are reported right after people have their oil changed or top off their oil. Remember- this isn't only subjected to oil vapor, but liquid oil as well. Lot of signs point to overfilling the oil as a major contributing factor. Regarding very frequent oil changes, it's well documented in industry that excessive maintenance can actually CAUSE failures just because it increases the risk of human error. Nothing in any of the oil analysis I've had Blackstone do shows my oil any less able to lubricate my engine at 8k or 10k than at 3k. At best, you're wasting money; at worst, you're increasing your risk of human error causing problems 3 or 4-fold.
Low AOS failures at high alt is interesting, too; lower ambient air pressures would lead to less of a pressure differential and a lower volume of air through the AOS. It should lead to higher % levels of oil vapor in the air (vapor pressure), but lower volumes of oil mist and other liquid oil, due to the reduced airflow pulling less oil up.
10-01-2014, 03:16 PM
#36
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10-01-2014, 03:54 PM
#39
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really? paid $30,000 for it with 33,000 miles on it and it was showroom condition 100%..was owned by the dealer's owner....you dont find them like that so easy, not po...just you find them like that very rarely that well maintained...oh and they gave me a 3/36000 bumper to bumper warranty..they also own the dealership where I buy all my trucks that helped..lol
10-01-2014, 04:34 PM
#40
Race Director
You service your car like you want but as long as you use an approved oil, and other approved vital fluids, and as long as you service thing at least as often as Porsche states, we'll get along just fine.
10-02-2014, 08:32 PM
#43
Drifting
Similar story to y'all, I was shopping for a car to replace my post-college beater and when I realized that not only could afford a Porsche, but was actually cheaper than buying a new miata once depreciation & resale value were included? Ended up putting 65,000 miles on that '04 Boxster S, and loved it so much I could only replace it with a newer Boxster S 
10-03-2014, 09:16 AM
#44
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yep..we had a Chrysler Sebring convertable and we were shopping for a new one, and they didn't have one ,but said they could get us one as they own about 6 dealerships. The Manager said we have a Porsche the owner had, he just bought a new one and wants to sell his. it was 3 summers ago and your right, it was the same price as the Chrysler and they hold value..it was a no brainer...mmmm...Porsche Boxster S or Chrysler...LOL...we were at the right place at the right time for a change
Last edited by Maclen; 10-03-2014 at 09:17 AM. Reason: adding
05-13-2015, 12:16 PM
#45
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Recently did a 100km fast run, on the highway, parked car , idled 5 mins and switched engine off for a week. When I started again puff of smoke came out which did not last long. Car has done 80k km and had recent AOS change. Oil was changed about 2weeks ago running a tad below normal level.No warning lights. Is this normal?