Blue smoke from exhaust at startup when car don't run for 2 days or more!
 

Hi, I have a 06 G35x with 73k KM and if I let the engine not running for 2 days or more, there's some blue smoke coming out of the exhaust at startup. It only takes a couple of seconds to the smoke to stop coming out of the exhaust.

Anybody had this weird smoke problem? Is it normal?

If I start the engine everyday, no smoke is coming out of the exhaust at all.

I'm still under warranty but if I bring the car to the dealer, they won't see the smoke because the engine will have run the same day or the day before...

Where can I look to see if there is some oil going in the engine? Blue smoke = burning oil right? Thanks!

when you turn a motor off one or more cylinders are on the intake stroke. It is then trying to suck in air fuel mixture. Although now that the engine is off the suction remains. If your valve stem seals are hardened, cracked, deteriorated whatever oil is on or around this valve stem will be sucked into the cylinder to be burned when you start it again...again this is just the start of an ongoing problem. It most likely will be many years and miles before you need to replace the seals.

Thanks for the info.

If the cylinder is on a intake stroke, the intake valves should be open to let the air come in...

Can someone explain where this oil come from? The intake plenum? Why is there oil in the plenum?

Maybe i'm missing something but I don't understand how oil can come from the intake!

That's the way crankcase ventilation is set up. You could get oil from:

1. The crankcase (can use a catch can to trap)
2. Past the valve seals
3. Past the cylinder rings (increased blow by possibly secondary to wear or transiently increased crankcase pressure - can try to change $15 PCV valve to see if it helps)

Leaky valve stem seals... been there, done that!

It only gets worse until you replace them.

Ok thanks guys! Is there a way I can show the problem to the dealer before my warranty goes out? I'm near the end of my bumper to bumper warranty and want to point all the problems I noticed...

that should fall under the powertrain which is 5yr/70K mile

but the only way to show them is to bring it to them and have it sit for a couple days before they start it