Mysterious white smoke from tailpipe

[300cd300sdl911]

OK so this doesn't make any sense to me. Hoping someone can shed some light or logic on what I experienced.

My ride home from work is about 35 minutes. After my oil was up to temp I did a couple of 2nd gear blasts around some corners for fun - nothing over 6k. About 5 miles down the road I get stuck in traffic for about 5 minutes. While sitting I look out my drivers side mirror and see clouds of white smoke pouring out the tailpipe - enough to feel sorry for the guy sitting behind me. Once the traffic moves I continue home. Jumped on 2nd gear hard a couple of times and came off quick to watch for smoke on decel - nothing. No smoke for the remainder of my ride home which was 20 minutes.

Checked oil this morning on the way to work (after reaching temp. with car running) and level is fine.....just above first mark on dipstick. No smoke on the way to work.

What happened?

[Porsche_monkey]

What year and engine?

[300cd300sdl911]

Sorry folks forgot to list: 1985 911 Targa 3.2.

[Rot 911]

For it to happen just like that it would sure seem to be that oil got sucked into the airbox. I know the oil level was not high, but not many other things it could be.

[crustychief]

Has it sat for a while recently? Maybe oil leaked down into the exhaust?

[ossiblue]

Originally Posted by Kurt V

For it to happen just like that it would sure seem to be that oil got sucked into the airbox. I know the oil level was not high, but not many other things it could be.

Your quote: "After my oil was up to temp I did a couple of 2nd gear blasts around some corners for fun - nothing over 6k."

I'd agree with Kurt.

[300cd300sdl911]

I appreciate everyones comments......no the car didn't sit for any length of time. The most difficult part for me to understand is this is the same drive I do every single day. Same blasting on the same corners and only yesterday did the car smoke. It's just not logical to me.

[JeremyD]

Did you let the engine brake the car? Was the 2nd gear run ups hard to 6000 rpms - then down to nothing letting the engine brake the car?

[300cd300sdl911]

JeremyD,

At the risk of sounding like a dumb _ss.......you know I just don't remember. Actually to be policitally correct I should say I don't recall - that worked for a couple of presidents should work for me.

I don't think I went cold turkey off the accelerator....but I couldn't swear to that in court. Do you think hard decel would have that effect. I did that a couple of miles later down the road and didn't see any smoke.

[JeremyD]

My 1987 Carrera - same 3.2 engines used to do that too.

It was intermittent. If I was hard on the accelerator - then used the engine to brake (or downshifted hard) then when I pulled up to a stop light (every so often) I would get a cloud of smoke.

Have someone follow you with a video camera - see if you are getting a puff of smoke when you shift. No way can you see it from the driver's seat.

BTW - mine turned out to be valve guides. Mostly on the exhaust side. My car had 56,000 miles at the time.

[Porsche_monkey]

There was a recent thread regarding brake fluid, but that doesn't apply to your car.

I would have to guess valve guides, depending on mileage, or on more positive note, oil overfill.

If it persists a leak-down would be in order. It is possible you a getting small puffs all the time that you don't see from behind the wheel.

Mileage? What oil are you using? Are you sure it was from the tailpipe as opposed to drippage burning off the exhaust?

[JeremyD]

valve guides won't show up on a leak down - rings will - valve guides - not so much.

Oil consumption will (although mine was pretty steady at 1000 to 800 miles per qt until the very end)

Puff of smokes are telltale -

[300cd300sdl911]

Pretty sure the smoke was from the pipe.....but all I did was to lean out the door and look. I'll check for drips later today. Oil is BP racing 20W-50. Car presently has 160k on the clock.

Guess, I'll just keep an eye on things, oil consumption (last time I checked 1qt in 1280 miles). I'll have the Mrs. tail me for awhile to check for puffs during shifting.

[stlrj]

Sometimes oil that gets past the rings overnight ends up accumulating inside your exhaust and burns off when you least expect.

[Porsche_monkey]

Originally Posted by JeremyD

valve guides won't show up on a leak down - rings will - valve guides - not so much.

Oil consumption will (although mine was pretty steady at 1000 to 800 miles per qt until the very end)

Puff of smokes are telltale -

Correct, but a good leakdown + puffs of smoke (probably)=guides

[robertb]

Why does the brake fluid not apply? No vaccum line for the booster for that year?

[robert walsh]

I think it is an air box issue, oil was perhaps forced into a false overfill situation, by hard cornering at 6k of G force, could push oil up into the air box, the same way it does when overfilled. I think guides or rings would show them selves far more consistently, with smoking related problems.

[robert walsh]

You really got me thinking on this one, I bet if you open the air box you will most certainly find oil, depending on the temp during the hard cornering and high rpm,s, again depending on wether your thermostat was open or closed, leaving more oil in the tank vs the cooling loop could, VERY, VERY, easilty result in oil overflowing into the box causing the smoke. Open and see, I'm very curious to know the answer.

[JeremyD]

I experience hard g-force laterally at the track and have NEVER experienced oil sloshing up to the airbox - even when almost to the top fill on the dip stick.

[robert walsh]

I agree with you Jeremy, but he said he had just left work and "waited" for the temp to come up, when on the track we always race on a fully tempered engine, I bet he just got on it a little to early and a little too hard, leaving the thermostat closed.