Today...for the second time...I noticed our LS had a puff of smoke from both sides of the exhaust on start-up. It was after we drove it a short distance then turned it off for about an hour and started it back-up. I do not think that the engine was at operating temperature...so...that could be something to do with it.

I cannot remember the conditions the other time this happened...it may have been the same scenario.

Any thoughts? For years, I've been a GM guy and as everyone knows, it's only a matter of time before the valve seals on a 305 or a 350 wear out and they start doing this. I really hope this isn't the case with the 3.9L...especially since our LS only has 57k on it.

I'm not at all panicked...just wondering the cause. Oh...one other thing...the first time it did it was before I replaced the valve cover seals.

TIA,
-Pete
02 LSE

Is it a black smoke or a white smoke that usually comes when the car is cold?

Sorry...I should have clarified that...it appeared to be a blue smoke. The reason I say it appeared...it because I saw it out of the rearview mirror.

Maybe I'm on crack...because now that I think about it...it was a really pale blue. Which...could have been thick condensation smoke from having driven it a short distance...turned it off...then restarted a short time later.

Still strange though...I only say this because the volume of smoke was more that I would expect from condensation.

Oh well...I'll just monitor it and see what happens.

Thanks for the reply.

-Pete
02LSE

Noticed this one time alittle over a month ago, car sits in the garage and I think I had just started it for the first time that day and glanced out the mirror and noticed like appeared to be blueish smoke. It kind of made me think but I figure it was some type of build like condensation or something and did not really worry much more about it and have not seen it since until today just on my way to work, but I'm not even sure if it was smoke or the way the sun hit the rear window and the tint.

blue is usually oil. could be a number of things. valve cover gaskets, pcv valve, etc.

Bad fuel injector caused this condition for me. Blueish-whitish smoke with a bad fuel smell when the care was shut off and restarted after sitting a spell.

"Puff of Smoke on Start-up"

at first, i thought that you were talking about what I used to do before driving to high school everyday. :D-~

but seriously, your problem sounds expensive $$$$$

Is the car a little hard to start after it sits for an hour or two after you drive it? That is a tell-tale sign of a leaking injector.