987.2 CS - Smoke on startup

[finestjammy]

Hi All

I know there can be the odd puff of smoke on startup, but I've never really had anything of significance in the 2 years I've had the car. On holiday at the moment and parked up on a grass on incline of circa 25% with the nose pointing upward, I've done this dozens of time. Went to start up the following day, today, and plume of white smoke, at least I think smoke, ensued. Not just a whiff/puff but a significant amount. Let if run for a little while and it cleared up. No sign of any smoke whilst driving. Parked up and Checked the oil level and it seems to have dropped a bit, I will check again later though as it doesn't seem to be the most accurate of guages.

Thoughts? Just a coincidence of incline and the way the oil was sat in the cylinders? AOS? Although wouldn't that be smoke all the time? Bore score?!?

Any help appreciated.

James.

[SkinnyPete]

I wouldn't worry about it.

Mine use to do this, no smoke for months then suddenly POOF the whole street is subject to a covering of white fog. Mine did burn oil though, about 200ml every 1000 miles.

[Bennachie]

Were there people there, watching?

Its always
worse when there is an audience...................

[flying]

Did have the same on my CS for quite some time probably not helped by the dealership having overfilled it a bit always seemed worse when the car was on a cross slope to the right and as was said quite embarrassing at times

[SkinnyPete]

Bennachie said:

Were there people there, watching?

Its always
worse when there is an audience...................

Fortunately it didn't do that when I sold it, otherwise I'd have sounded like a usual car salesman "they all do that sir".

[finestjammy]

Cheers guys. Been driving the father in laws Grand Scenic, yuck, and will be back with the Porsche in an hour or so. Let's see what happens. I think/hope it was a coincidence of angle, weather, moons aligned that caused the smoke. Fortunately not a crowd, very embarrassing

[chriscoates81]

I had a fair amount of smoke when I started my turbo tonight at work. I'm putting it down to rain dripping thru the engine bay vents onto the exhaust. Had it been raining when you noticed it?

[finestjammy]

chriscoates81 said:

I had a fair amount of smoke when I started my turbo tonight at work. I'm putting it down to rain dripping thru the engine bay vents onto the exhaust. Had it been raining when you noticed it?

I don't think it has been raining. Started it up after leaving it for 5 and half hours and it seemed fine. I think there just must have been a fair amount of oil pooled due to the angle I was parked at. We'll see what happens. Thanks.

[s3 akr]

I've had my PCR for a year (covering 2600 miles in that year, 32k on it now) and it has done this twice - once about 3 months ago having not long been used, then again about 2 weeks ago having been stood overnight. If it does it a lot there are youtube videos on it and a repair guide - something to do with an issue with the Oil/Air separator (search "Porsche smoke"). I've now exhausted (no pun intended) my knowledge on this topic!!

[Rockster]

finestjammy said:

Hi All

I know there can be the odd puff of smoke on startup, but I've never really had anything of significance in the 2 years I've had the car. On holiday at the moment and parked up on a grass on incline of circa 25% with the nose pointing upward, I've done this dozens of time. Went to start up the following day, today, and plume of white smoke, at least I think smoke, ensued. Not just a whiff/puff but a significant amount. Let if run for a little while and it cleared up. No sign of any smoke whilst driving. Parked up and Checked the oil level and it seems to have dropped a bit, I will check again later though as it doesn't seem to be the most accurate of guages.

Thoughts? Just a coincidence of incline and the way the oil was sat in the cylinders? AOS? Although wouldn't that be smoke all the time? Bore score?!?

Any help appreciated.

James.

Under some operating conditions the AOS can allow considerable oil vapor through and this ends up on the intake walls. If the engine is shut off before this oil can work its way into the engine proper this oil will drain down into an open cylinder or on top of the closed intake valves. Next cold start there will be smoking as this oil doesn't burn completely because of course the engine/exhaust is cold.

If the car is parked on an incline what can happen is the hose from the AOS to the intake, this hose which can have some oil in it, and there can be some oil puddled even at the port where the hose connects to the intake manifold, is these areas contribute a fair bit more oil to the oil that is on the intake walls and you can end up experiencing more smoking than "normal".

While noticeably more smoking it is still "normal" for these engines if the smoking is very short lived that is starts to taper off almost as soon as it starts and the engine doesn't manifest any untoward behavior and the CEL remains dark.

The oil level being down is probably an artifact of the way you checked the oil. The best oil level check is one that comes after the engine has been run long enough to get the oil fully up to temperature which can take minutes of run time then shut off and allowed to sit a while. My experience over the years with my 2002 Boxster is the amount of time to sit after being shut down is the time it takes to fill the gas tank. An added bonus is the station pump island apron is probably pretty darn level so one gets a very good reading of the oil level.

The next best time is after an up to temperature engine was shut down and allowed to sit unused say overnight. But remember: When checked cold one can get an oil level reading that shows the oil level down a bar or two from where it was when the oil was checked hot. All that is required in this case is to avoid adding oil for a cold oil level reading that is just a bar or two down from the max line because when hot the level will be at the max bar line which is where you want the oil level.

[finestjammy]

Thanks for the detailed response Rockster. A few more cold starts and it seems fine now, no smoke what so ever. The oil level seems constant now too. Very odd that it has never happened in 20 months and then suddenly it turns in to a smoke machine.

[ChrisW.]

The same thing happened to me in my CR after a day at Spa. The car had been parked on a quite acute rearwards slope.

When I started it up the following morning I wondered what mischief I had done.

In fact nothing. It only ever did it once in 34000 miles during which time between oil changes, I added less than 1 litre of oil.

But because I do a lot of track days, there were quite a few oil changes !

[DarkMatter]

Good explanation Rockster.

I've found that more often than not the short duration smoke cloud occurs when the car has been started and stopped almost immediately (so it hasn't even settled to a normal idle let alone reached operating temperature) and then left for a while. I've assumed that some unburnt fuel has washed some oil out of wherever it was hiding.

[rdjohn]

I have had this occasional problem with a 987.1 for the 6-years I have owned it. At first it really worried me. I had the car serviced by Hartech in November and it seemed to stop. Low and behold starting on Sunday and again this morning, it suddenly returns. It has only ever happened from cold.

I suspect that it is a cunning widget installed by Porsche to encourage owners to go along to their OPC and pay them some cash. When Hartech do a service and borescope check they report that everything looks very normal.

I no longer worry about this issue.

[finestjammy]

Mine is actually at the OPC today to look at a bit of hesitation and judder on light throttle. I mentioned the plume of smoke, as I thought I had nothing to lose with it being under warranty. We shall see.