2011 Porsche Panamera S- excessive oil

[WasEYEconned]

Please would anyone able to do so pass comment on my Pana purchased with 39000 miles and full history 3 months ago. I have now covered 3200 relaxed miles and topped up the oil (0w 40) 4 times !. 800 miles a litre of oil seems a tad high ?

It is under warranty, purchased from a main dealer, albeit Bentley rather than Porsche.

Thank you in advance.

[itcaptainslow]

The manual should have a tolerance published within it of how much oil usage is acceptable.

[10penceparalyzed]

I'm no Porsche expert but that's excessive for any modern engine, expect a struggle to get anything done IMO no doubt the line "its within acceptable parameters" will be trotted out.

[WasEYEconned]

Thank you for the replies above.

I have since googled and it seems that it is a very common problem. The acceptable usage is 1 litre per 620 miles. There have been court cases in america regarding this. Some say it is just mobil 0w 40 and change to to the unrecommeded 5w 40.

[Rockster]

WasEYEconned said:

Thank you for the replies above.

I have since googled and it seems that it is a very common problem. The acceptable usage is 1 litre per 620 miles. There have been court cases in america regarding this. Some say it is just mobil 0w 40 and change to to the unrecommeded 5w 40.

Oil won't make a difference. Best to stick with an approved oil. Don't know where you are but if it gets cold -- -25C and colder -- Porsche says to run 0w-40. Frankly, I'd run 0w-40 even in a bit warmer temps, like if it was going to be below 0C.

Usage affects oil consumption. Lots of idling, or lots of high RPMs. Running the oil too long can do it. The oil gets contaminated with various compounds including water. This contamination causes the oil to foam and vaporize more readily -- the interior of the engine probably has an oil fog at higher engine RPMs anyhow (the engine can have a couple of liters of oil in suspension at higher engine RPMs) -- and this oil fog/vapor can be lost through the AOS (air/oil separator) due to the inefficiency of this item.

You won't see any oil smoke because the engine and exhaust are hot so any oil vapor routed to the engine while it is operating will be pretty much consumed completely. You can't blame the soot that collects at the exhaust outlets because for every gallon of gasoline burned the engine generates around 19lbs of carbon, most in the form of CO2 but some in the form of soot. A few drips and drops of oil over a long time won't amount of any change/increase in the level of soot at the exhaust tip.

What you can see sometimes is some oil smoke upon startup. This is clearly an indicator the AOS is passing oil to the engine -- intake -- while the engine is running for when the engine is shut off this oil vapor -- which has collected as oil droplets on the intake walls -- then drains down into an open cylinder or on top of the closed intake valves. Upon cold engine start this oil is incompletely burned -- cold engine/exhaust -- and the smoke is the result.

My point is there is nothing special about just before you turn the engine off so this routing of oil vapor to the engine is a constant thing.

Thus unless you spend hours idling the engine, or drive everywhere at redline, or run the oil way too long -- I have found 5K miles is a pretty good change interval -- or overfill the engine, the engine oil consumption is probably the fault of the AOS.

Not much you can do about that. No way I'd recommend you replace the AOS. The new one might be no better and could be worse.

Just live with it would be my advice. Carry a spare bottle or two of oil and check the level often and keep the level topped up but of course do not overfill the engine. Be aware -- if you are not already -- that the oil level cold will be higher once the engine is up to temperature so if you can check the level cold and it is down a bar or two that's ok. (My Boxster's cold oil level will be 1 or 2 bars higher when checked hot vs. when checked cold.)

Oh, if you want you can accurately track the oil consumption and if it gets too bad then you could possibly have this "fixed" under warranty. You'd have to find out what kind of tracking is required and be disciplined doing this.