2002 Q45 Oil smoke when starting

[carnut]

70,000 miles, maintained by the book since new, burns some oil (needs a quart added between 3,750 oil changes, which I'm told is normal). Quaker State 5W30 oil, car in San Francisco CA area.

Blows quite a big - a few feet in diameter, cloud of blue/oil smoke on startup after parked for several hours (e.g. overnight).

1. Would it be valve guides or something simpler like a stuck PCV etc valve?

2. Assuming it's serious, what are the manufacturer's responsibilities in terms of fixing emission problems on such low miles/well maintained, high-end car? The full warranty ended last year, I did not bother to claim it as the smoke was very small a year ago (but I realize that those engines can be quite oil burners, I talked to a guy who had the 2002 Q45 engine replaced under warranty for excessive oil consumption). Are there any emission warranties/responsibilities, specially in California?

thanks for your help

George

[Q451990]

I don't think it would have any coverage under the emissions warranty unless it fails a test. At this point I would work with your dealership and the factory to try to get some "goodwill assistance" with your issue...

Heath

[Q45tech]

As a test, try a thicker oil.............. 10w40 a quality brand such as Valvoline Extended life. If the smoke stops or diminishes then change it again for Mobil 1 Synthetic in a 40 weight.............in NCA {SF} the cold weight is immaterial 0,5,10 just not 15 or 20

Who suggested Quarker State not a brand I would think is suitable to get 300,000 miles............15% of your oil [low quality conventional] evaporates away............a full top of the line synthetic will lose half [7%] as much during the same period.

My 307,000 mile Q started smoking a little last winter on 10w30 and a change to 10w40 seems to have reduced it significantly.......however it is much warmer............only cold weather will prove it.

[Jesda]

Well, are you noticing a lot of oil consumption?

[carnut]

Thanks guys,

I'll try a thicker oil next time I change (Quaker St 5W30 is what the local Infiniti Dealer in Santa Clara has been putting in it, so I do the same when I change the oil myself). Does it mean you expect the valve guides problem and thicker oil not to leak down into the combustion chamber that much?

I had a hope for something cheaper to repair like a PCV :-). It would sure be nice to start smoking due to internal engine wear at 300k, not 60-70k

Regarding consumption question - as I stated I add 1 quart between 3750miles changes - with mixed driving half way between changes (consumes 2 quarts for 3750), with long highway drives it drops to about 1.5 quarts.