2012 Subaru Impreza Oil Usage - Is it a generic design flaw

When a new car consumes a qt of oil in 2k miles, it would naturally concern most owners, but the reality is that every car maker with which I am familiar claims that this is a normal rate of consumption. That is undoubtedly the stated policy in order to avoid many warranty claims.

In fact, when new Audi owners complain about even higher oil consumption rates (1 qt every 600 miles in many cases), they are told that this rate of consumption falls within Audi’s acceptable rate of oil consumption. Bottom line=no warranty assistance from Audi.

All of that being said, the way that an engine is “broken-in” has a lot to do with how much oil it will consume during its service life. All too many people “baby” the engine too much during its first few weeks or months, and being too gentle with the accelerator can actually make it impossible for the oil control rings to seat properly.

The way that I have broken-in my engines for the last 40+ years is as follows:
After the first week or so, I make sure that I do at least one “brisk” acceleration run each day–after the engine is fully warmed-up.

No–you shouldn’t floor the accelerator at traffic lights. Instead, when you are already rolling along at 30-40 mph, push the accelerator forcefully, so that you can rapidly accelerate to 50 mph or more. A good place to do this is on highway entrance ramps.

When you do this, you force the piston’s oil control rings outward, thus making full contact with the cylinder walls. Doing brisk acceleration runs 10-20 times over a period of a few days is usually all that is needed to properly seat the oil control rings.

So–if you have driven the car very gently, I urge you to try what I described above. By doing this with all of my new cars, I have been able to drive them for well over 100k miles with a rate of oil consumption of no more than 1 qt every 4k miles. (Actually, there was one exception, but luckily for you, you don’t own a Volvo.)

Also, while it is unlikely that the PCV valve is defective, it would be worthwhile to check it, as a jammed PCV valve will cause increased oil consumption.