HansPW

I am getting a bit (sometimes a lot) of smoke on cold start. Not all the time, maybe every forth or fifth time. Has anyone else has this? The car was recently purchased, but was used with just over 3000kms on it. Very interested to hear if anyone has exploring with this is our if it is "normal"

Alan C.

Normal. Most have experienced it. I'd be happy with only every fourth or fifth start.

HansPW

Wow, huge sigh of relief. Thanks. I am going to double check with the dealer anyway, but i never fully trust their responses. Much appreciated.

jlanka

Totally normal. One theory I've heard is it has to do with the cylinder position when it was last shutdown.

Maverick787

Enjoy the mystic.

911turbos

It's normal.

MAQ

Happens to me on every cold start. Normal.

bronson7

Normal, not in my case though. Have yet to see much, if any. Maybe mine is not normal. lol

Alan C.

My 11 GTS never smoked and had the best oil analysis of any of my cars.

Dude-

Im with you Bronson, is it normal NOT to have smoke at start up? My 14 was common but for some reason my 16 does not smoke. Not to mention the exhaust note is a little different from my 14. It pops a lot harder and feels a tiny bit stronger. Was there a mapping change recently?

GregJGT3

The smoke is oil from the crankcase getting past the rings. Race engines are typically fit with a loose clearance between the piston wall and the rings/piston. This allows for swelling of the piston and ring when the engine gets up to temperature without creating too binding a fit. Less resistance means better performance. So the ring/piston fit is set up ideally for when the parts are hot and "swollen." When you start up a cold engine the ring fit is not ideal/sloppy and you get some oil past the ring into the combustion chamber and then out the exhaust as smoke.

HansPW

The dealer said it was also a result of the flat six set up of the engine as all of the oil cannot drain to the pan, some will remain in the chamber. Seems to make sense.

GregJGT3

Well, there isn't supposed to be any oil in the combustion chamber. From the piston ring down to the crankshaft to the oil pan yes. But not past the piston ring where it will combust with the fuel. This is why an old, tired engine with worn rings will smoke. The job of the piston ring is to seal the combustion chamber from the crankcase. When the engine gets hot all the parts expand. If the ring fit is tight this creates increased friction. Increased friction means more heat and more energy expended to move the piston per stroke. Thus passing less energy on to the crankshaft to be converted to power at the driveshaft. Race engines want to convert as much energy to the rear wheels as possible and produce the least amount of wasted energy. You can spend a lot of energy moving Pistons at 9000 rpm... So the ring fit is intentionally loose and dependent on heat expansion to seal the cumbustion chamber effectively. That way the friction is minimized by accomplishing a ring seal with the least amount of friction. Hence some oil gets past the rings at cold start when the rings are not sealing efficiently.

bronson7

All makes sense to me. Pretty simple when you think about it. Thanks for the explanation.

WernerE

Same here with a 2015 - never any smoke.

Curious: Does the tranny in your 2016 still make "metal music" like your 2014?