long_beach_968

Somebody memntioned the "blue puff" seen at startup on our cars in another topic. I have seen this on a few of the 996's we have had over here. I would also expect this from my 60k mile 993 as I have seen it on a lot of other air cooled 911's. I have only seen it once in my ownership of this wonderful vehicle. So I was wondering if there were any thoughts on it either way and what percentage of you see it or dont.

Dan V

This is funny!! I've heard of this happening mainly on cars that have sat a while. Finally yesterday, I remembered to look for it. Car had not run for 3+ days (maybe not long enough?). No sign of any smoke at all on startup. Car has 68.3K, and very low oil usage.

tj90

I see it on approximately 1 out of 10 of the start-ups and my car burns very little oil (113k mi car with 15w-50). I did one time start the car while the front of the car was jacked up doing bumper reconditioning. The car was jacked up in the front for about a week. Man, it was the most amount of smoke I have ever seen. I think the angle of the block can make the smoke worse....

SwayBar

A 'blue puff' is not necessarily a bad thing.

When the engine is turned off, there is no combustion to seal the rings against the cylinder as the engine winds down. As a result, oil which is on the cylinder wall(s) is 'allowed' to escape/sucked past the relaxed cylinder rings and onto the top of the piston and into combustion chamber. That oil will remain there until the next time the engine is started, whereupon it will be instantly burned off, and seen as a a visible puff of blue smoke out the tail-pipe.

More than likely, nothing is seriously wrong with the engine; if anything, maybe it's just a little 'tired'. However, if oil consumption is a non-issue, I wouldn't worry about it, at all.

ceboyd

what about 'white puff' instead of 'blue puff'


I notice a white puff at startup sometimes but NOT a blue puff (then again, I don't always look either)

SwayBar

White smoke is indicative of water, so maybe there was condensation being burned/boiled off, maybe in the exhaust.

amfp

Only occurs with me if car sat for weeks, which is normal.

ceboyd

lol.. living in humid chicagoland.. that makes a ton of sense!!!!!!

Mark in Baltimore

I think I've seen a puff of smoke maybe two times in the four years that I've owned this car.

Bull

I have seen the "off-white" smoke with every 911 I have owned since 1969, but very infrequently, like when the car sits for a long time.

jimbo3

To add to TJ90's point- First and only time that mine blew some smoke at start-up was after it was parked it on the driveway for a couple of hours. Driveway slope is 3 1/2 feet in 30. Oil consumption is considerably less than one quart in 2000 miles.

Jim

Dr. No

Seen it only under two circumstances: (1) car sat for weeks (2) car sat on sloped portion of driveway.

JasonAndreas

Most of the time just allowing the engine to idle for 30 seconds before you shut it off will stop most if not all startup smoke.

ceboyd

why is that?


I used to sit for like a minute back when I had a turbo car but now only run it long enough to remove my helmet, gloves and belts before shutting it off between sessions at the track (dunno if that is 30 seconds or less or more)...


..and in street no waiting....

sidned

The only times I've seen it is when I haven't had time to let her idle for a few seconds before switching off. I usually let her idle and never see anything upon the next start up.