Do you see a puff of bluish smoke on start up or once you rev the engine after it has been idling for awhile? IF so that could be valve guide seals.
Are you driving the vehicle at autobahn speeds? You'll see an increase in consumption at these speeds.
Do you drive the highways often?
Do you remember how the valvetrain looked when you replaced the valve cover gasket? How does it look under the oil cap?
Do you smell oil burning inside the cabin? If so that's typically indicative of an oil leak at the valve cover gasket (Passenger side towards rear).
Other oil leaks check out? Rear main seal, oil pan, oil filter housing gasket?
Do you see a puff of bluish smoke on start up or once you rev the engine after it has been idling for awhile? IF so that could be valve guide seals.
There is some smoke when revving after idling. Not a great deal and I would not say bluish necessarily.
Are you driving the vehicle at autobahn speeds? You'll see an increase in consumption at these speeds.
No. Nothing in driving behavior has changed over 2.5-3 years of this steady and incremental decrease in oil efficiency. There is nothing sudden about this. Gradual and incremental.
Do you drive the highways often?
3-4 times a month. Not very long distances. 10-30 miles maybe.
Do you remember how the valvetrain looked when you replaced the valve cover gasket?
I just know the mechanic I use has generally always thought my engine looked good for its relative age.
How does it look under the oil cap?
I see no evidence oil is being prevented from doing what it does, including drain back.
Do you smell oil burning inside the cabin?
Never once.
Other oil leaks check out? Rear main seal, oil pan, oil filter housing gasket?
Not there yet. Been pouring rain here.
