Maclen

Macster, no alarm issue last night now I have one more question...it was cold yesterday morning,
wife only drives 1 mile to work, she started the Boxster let it warm up for a while and drove to work, car set all day and the afternonn was warm, when she started it 9 hours later she got a big puff of white smoke, car ran fine..
no warning lights, she shut it off and restarted..no smoke, car ran fine no smoke after at all..condensation?? never has done it before. also I drove it hard after with her behind me in other car...nothing..no issues, coolant level..no change.

LexVan

Puff of white smoke that quickly clears is normal of the flat six design. Don't sit and let the car idle to warm up. Start it. Drive it. Keep the revs below 4,000 till the coolant and oil come up to temp (180-ish).

Maclen

she said it was a big puff cloud, but it did stop quick, temp never goes above 175, why never before?
I thought it was due to the weather

Maclen

anybody else have a suggestion please? it was concerning ..lol

LexVan

Keep an eye on your AOS. Quick test- at idle, remove the oil fill cap. Does the cap come of easily? That's normal. Hard to pull off? Failing/failed AOS.

LexVan

Women can't measure. That's a good thing for men. LOL!

You want the car to come up to operating temp (175-180) before getting into the higher revs (above 4,000). Oil, coolant, and gearbox. Sitting and idling does not warm up the car's parts in harmony, waste fuel, and can cause fuel dilution in your oil.

zedcat

Lots and lots of threads about brief smoke on startup. My 986 S (M96) does it maybe 1 out of 10 starts. Both of my 987.2s (9A1) did too. I never saw a correlation to temp or time sitting, so I just quit worrying about it.

Maclen

LOL!!!!!!!!!!!..yes it is, if it was AOS wouldn't it run a little rough and smoke driving?

LexVan

It could. Depends on the level and current stage of failure. Again, a puff of white smoke on cold start up is n o r m a l.

Maclen

ok..thats what I have read, but only 53,000 on it and have nver had it happen before, I will try the oil
cap test, if it unscrews easy it ok then..thx

extanker

po smokin on start up...sometimes cold sometimes hot,sometimes alot sometimes not. disregard all the myths about idling for 30 seconds before shutting off,parking on a 34 degree left hand slant,parking on a 23 degree right hand slant or parking in your neighbors drive wayits embarrassing but not a need to worry until it happens way more often or oil usage goes up

sjfehr

Here's the deal: Porsche designs these cars with tight engine tolerances AT OPERATING TEMPERATURE. At lower temperature, the seal is much poorer (incidentally, same reason you shouldn't flog it until it warms up.) It's a flat 6 with oil everywhere, so these seals also help keep oil out of the cylinder.

When you shut it down before it has time to heat up, small amounts of oil seep past the piston rings and give you a brief puff of smoke on startup. (When it's running, small quantities of oil seep past, but you don't notice until you let it sit for a while and a large quantity has time to accumulate.) I found this to be completely repeatable with my 986S: park it cold, big puff of smoke. Park it hot, pretty much nothing. If this is what you're seeing, it's normal and not a problem.

Maclen

thank you sjfehr

Macster

Others have already responded, so most of what I have to say will just be a repeat.

The type of usage the car received the other day will almost ensure the engine will briefly smoke upon a subsequent cold start.

As long as the smoking is brief, it stops as soon as it starts, the engine is not exhibiting any untoward symptoms (exceptional rough running, or a hunting idle) and making no strange noises, and the CEL and other warning lights remain dark, the smoking is normal.

Let me add that with winter coming some will begin to see in some cases considerable moisture condensation upon or shortly after a cold start. This is also normal. One can distinguish between oil smoke and condensation as oil smoke hangs together even if there is a breeze. Condensation dissipates even if there is no breeze.

I do not subscribe to the theory the oil gets past the rings when the engine is shut off. When the engine is shut off the area toward the rings is hotter than lower down where there can be considerable oil -- courtesy of the oil jets which spray copious amounts of oil at the underside of the piston.

However, oil flows away from heat, not towards it and certainly not past/through very small gaps around the rings.

The oil that produces the smoking comes from the AOS is my theory.

This thing just doesn't work very well at least part of the time.

What happens then is crankcase fumes laden with oil vapor are passed through the AOS with the oil vapor remaining in the fumes. These fumes have to make a sharp turn upon entering the intake.

This sharp turn acts like a crude but in this case somewhat effective air oil separator and oil collects on the intake wall.

If the engine continues to run this oil will get pulled into the engine where it is burned and no one is the wiser. There will be no smoke no signs of this oil being burned. In some cases I suspect the AOS is lousy enough it can actually account for "excessive" oil consumption.

But if the engine is shut off before this oil on the intake walls makes it into the engine then as the intake warms up from heat soak this oil flows down and into the engine into one or possibly two cylinders, or if the intake valves are closed collects on top of the intake valves.

Upon the next engine start this oil is what turns into smoke.

BTW, my '02 Boxster just suffered its 3rd AOS failure the other day.

This failure a bit different than the others.

The engine has been running just fine. I have been driving the car quite a bit. The replacing of the noisy convertor which also replaced a sub-par performing converter, has the engine running as good as it ever has.

On the way to see Mom and Dad and I stopped at a stop light. Upon taking off I happened to glance in the rear view mirror and noticed a huge cloud of smoke behind my car. I thought the thing might be on fire, or a water hose broke.

I checked the dash and no warning lights, water temp gage was ok, the engine was running ok.

I continued to make the turn and drove two blocks to my next turn. Upon pulling away from this stop light the smoking resumed. I knew then what was going on and turned around and headed towards the dealer.

As long as I was reasonably gentle with the throttle the engine didn't smoke. But I got caught at a particularly nasty intersection and had to wait for what seemed like minutes before I could turn and upon pulling away the engine smoked something fierce. The engine also exhibited a bit of rough running. Still no CEL though.

Decided not to push my luck so I pulled into a parking lot and called AAA road side assistance for a tow.

The car is in the shop now getting a new AOS, its 4th. Also, it is getting an oil/filter service -- time now with 285K miles for another 5K mile oil/filter service -- and new plugs. I found out the plugs have been in service for a bit over 100K miles. (I lost track of time/miles what with all that has been going on the last 3 years.)

Let's see… the 1st AOS failed at 80K miles. The 2nd failed at around 180K miles. The 3rd failed at 285K miles. Guess I had better start saving up for the 5th AOS due probably in another 100K miles.

ep3_lol

One thing I'll add- some people see this frequently, others rarely. It happened to me maybe once a month when I drove the car daily. As long as it is oil smoke and is stops quickly there is nothing to worry about.