911fiend

I couldn't find a post on this but I'm hoping someone else has seen it. I've had my 2001 996 for 3 weeks. And so far there have been 3 times (that I noticed) where after hitting around 6500 rpms and upshifting a huge plume of bluish smoke farts out the back. I had the o-rings and cam cover seals replaced before I got it, so maybe the o-rings haven't seated properly yet? Has anyone else seen this?

CosmosC4S

Just a high possibility that it's one of the common "normal" characteristics of our engines.
Do a search on white smoke, and you will see some threads on this issue.
Same thing scared the crap out of me when I first got mine.

Were you doing some sharp turns before/with the hard acceleration?
And If your oil level is at max, those could contribute to the "blue smoke" as well.
What about first startup the next day? Is there the same puff of blue smoke, just for a few seconds?

911fiend

Yes the first huge plume happened after I just came out of a sharp decreasing radius on-ramp curve and floored it. The second time I saw it was up in the mountains after tons of twisties then flooring it again. Both times the smoke was a dark blue. Then we took a break (I didn't let it idle for long like other posters suggested), and when I turned it on the white smoke puffed out. I understand the white smoke on startup is normal, but not sure if the blue smoke at speed is. It's pretty embarassing to be farting around like that

911fiend

Ok, so I talked to the mechanic that worked on the car. He was saying that dark blue smoke like that is usually excess fuel burning off. From what I understand, he said that when you're going full throttle, there's a switch that opens up, and if you pull off the throttle rapidly (i.e. when upshifting) some fuel may leak in before the switch closes, causing it to burn off when the throttle kicks in again. So ultimately he's saying it's fuel burning, not oil. He said oil is usually white in color, which makes sense since that's what I see when I start the car again after a hard drive. He said to pull off the throttle slightly before I upshift, and I shouldn't see it... Hopefully this makes sense to someone, I have a lot to learn....

Tippy

White = coolant/water
Blue = oil
Black = fuel

A switch that cuts off fuel?!?!

Dave Howerdel

Dark blue smoke has always indicated oil burning, not excessive fuel(rich). White is coolant/water vapor. Also, he said to reduce the load on the engine and you won't see smoke..A bit like don't put a boat in water and you won't see it leak. I'd bet my money on blowby and bilge pumps

What you've been told doesn't sound right to me.

carpundit

Did you hear the mechanic correctly? Blue smoke is oil.

He wants you to lift off the throttle before you shift? Um, isn't that what you do anyway? I mean, my 996 is a Tiptronic, and that's what it does. My Bimmer is a standard and that's what I do.

Steven C.

If you are going to track, run in the mountains or drive like hell what I am told is that the oil needs to be below the full mark. Probably half way down to keep oil out of the separators. Will not hurt anything but is embarassing. Happened to me first time on the track and went away on the drive home.

Kirk S

Around '01 or '02 model year Porsche made a change to the dipstick (and presumably the electronic oil level sending unit?) so that the oil level in the 996 motor was kept lower than before due to symptoms like you describe and others have mentioned in this thread.

So their may be merit in the seemingly counter-intuitive idea that if yours is a 996 prior to this oil-leveling change (if what I heard is true) then you indeed may want to run with oil somewhere below the official "full" mark.

Mine is an '02 C4S and what I was told (by dealer tech I think) is that mine has the updated oil level changes....so when I tip mine up it's not really "topped up" like it would be for an earlier model...the dipstick and gauge just fool me into thinking it's topped up.

Of course, this could all be bad data too.

Kirk S

I probably have the year of the oil level change wrong (if it's true at all) as my engine was replaced (RMS) in Aug '04....so I sort of now have an '04 3.6L motor I suppose(?)

Ray S

It does not sound normal to me. I own two Porsches with M96 motors and neither has exhibited "blue smoke" (or any color smoke) in the situation that you describe (regardless of oil level).

I occasionally get a little smoke at start up from the Boxster (1 out of 100 starts) but that is the only "smoke" I ever see.

Tron999

Maybe you should check out another mechanic. He doesn't seem to know his smoke colors well.

911fiend

At this point my oil level is down 2 notches. I'll keep an eye on if the smoke still happens at this level. If so then I'm taking it to the dealer and let you know what they say.

Steven C.

FYI My knowledge came from the Ruf guys.

ElTorrente

Burning oil is not "normal".

Some people around here go thru a quart of oil every couple thousand miles, and think it's no problem at all - but I would be truly horrified. Burning oil means improperly sealed piston rings, and your pistons will prob be filthy, plus you send combustion gases into the engine, not to mention of course you have a little lower compression and less power than you should have.