So as someone who owns a 2013 2.0L Impreza affected by said issue... No, it does not take multiple top-ups to not run dry. The light comes on. After 5-6k miles at which point I have to add 1 quart to get it back to the middle of the dip stick. Subaru has not been experiencing many engine oil starvation issues with these motors at this interval, only customer complaints of excessive oil consumption. They tested it and deemed it wasn't a big enough problem to fix, which is outlined in the class action paperwork. Yes, companies make stupid decisions sometimes (like VW) but that doesn't mean we just ignore everything and continue changing oil at 3k miles like cave men. Waste your money if you want, but it's just simply not necessary anymore. You're arguing for the sake of arguing without doing proper research first.

And yes... Of course a new DI engine is going to suffer from intake sludge. That's how the design works... Just like how belts get old and crack, and spark plugs degrade. This is a general maintanence item, walnut blast the intake every 30k or whatever and you're fine. The benefits out weigh the extra maintenance needed and it has absolutely nothing to do with oil change intervals nor the boxer engine configuration. Stop spreading misinformation like a disease.

 

I disagree that having to walnut blast the intake every 30K is anything but design flaw and quality control failure.

I suspect that on a $20K car such $500+ out-of-pocket procedure will never be done. Plus, with Subaru engine configuration you will probably have to take the engine out to get it done.

 

Stohlen,

Your take on the "walnut blast" as becoming a routine maintenance item on GDI engines is an interesting one. I'm not disagreeing with you, and the benefit may well outweigh the cost.

But, just out of curiosity, what's the approximate charge for such a maintenance procedure, and do you see the cost coming down as these are done all the time given the staggering number of GDI engines that will soon be out there over 30K miles?

I suppose it beats the hell out of having to pay for an annual Ferrari service, or having to remove the cab of an F-350 diesel to change the spark plugs.

 

Considering the intake is literally staring you in the face when you open the hood, no, you would not.

Cost can vary, especially because the amount of work involved is related to number of intake valves as well as how difficult it is to remove the intake manifold. The BMW N54 6 cylinder motor costs roughly $400-500 for a blast at a shop. I don't see the cost coming down too much, because it's mostly labor related. I compare walnut blasting to a timing belt chance. You can ignore it but it's best if you don't. Conversely, some OEMs have invested in additional technology to prevent this issue, similar to the addition of a "maintenance free" timing chain. Subaru for example; added a second set of fuel injectors in the intake to wash the intake valves. This system only activates at idle and during cruise when peak performance isn't important. It is a costly addition but likely something we'll see on cheaper DI motors as owners are more likely to ignore "optional" maintanence than premium brand owners would like JLR or BMW.

 

I'm sure you meant glow plugs, it being a diesel.

If (if) 30k miles is found to be a common interval and if (if) GDI engines become mainstream and if (if) no solution is found to preventing intake valve carbon build up, then maybe (maybe) media blasting done by garages will become part of normal service. Some clever soul will invent a device that combines a camera, media delivery tube and vacuum all into a flexible wand that could be guided down the intake tract to the affected valve. Not rocket surgery. Maybe (maybe) it's already been invented.

Alternatively, and similar to the method used by modern diesels and DEF fluid to give themselves a good scrubbing, possibly future GDI vehicles would incorporate a device that sprays a minute quantity of intake valve cleaner when the car senses a contamination issue. Maybe it could be combined with the oil vapour coming from the crankcase or combined with EGR flow.


Naaaaah, engineers are stupid and overruled by bean counters and guys in suits.

 

Duh, why yes! :-)

 

I am sure tires will last very long time on flying cars, but this hardly helps us with today's problems.

 

I don't think so. Landings are very hard on tires. :-)

 

Subaru uses a hybrid port/DI system, at least in the BRZ. I remember when they announced it I thought this was a clever "best of both" system, and might also forestall intake valve oil sludge problems. Whether this turned out to be so, I don't know.

 

I think Audi is moving toward the same thing. They've been using DI engines long enough now, that they have real problems showing up.

 

I am willing to bet Subaru engineers are in the same boat. This is why we shouldn't blindly follow such recommendations, after all these are just educated guesses and fudge factors all the way down.

There is long-standing industry history of bad predictions with 'lifetime' fluids. To me, ultra-long service intervals are manifestation of the same problem - hubris based on improper testing. You, the owner, end up paying for this.

Fundamentally, there wasn't breakthrough in the oil chemical industry to allow engine oils last that much longer. The last breakthrough was synthetic oils and it was during late 80s. Since then, oils didn't miraculously improve. As such, suddenly increased recommended service intervals should be viewed with suspicion. Especially in context of moving to 0w20 from 5w30.

 

The intervals didn't 'suddenly' increase and by and large it was not due to the usage of synthetics.

The S-type with either the 3.0, 4.0 or 4.2 engines have had a 10K change interval since their inception in 1999. No requirement or expectation of synthetics.

Even SWMBOs former 2003 Civic had a 10K mile oil change interval using standard dino oil. There's few engines that are more bulletproof and hard working than those little 4 bangers. The fact that even the droopy pant yoots with fart can mufflers can't seem to blow them up says a lot.

I suppose if you had one of those lowly cars you wouldn't change the oil in them either.

 

Actually, I too have 2013 MT 2.0L Impreza (winter beater) with a hand-built engine that doesn't burn any oil. Not a drop. After prolonged battle with Subaru, they were forced to fix this issue. You can probably tell that I don't quit easily...

I don't know of a single engineer in my class of 50+ who would knowingly sign off on such flaw. Engineers don't set out to release shitty products, it happens despite our best efforts. Once they knew about the problem, Subaru engineers developed a solution (redesign of scraper rings), and then it was DECIDED FOR THEM that it isn't big enough problem to fix for all impacted customers. They only fixed it for a subset of customers who were forceful in getting them to fix it. Since I was pretty much at 'ground zero' of this issue with my very early 2013, I can tell you with authority Subaru didn't discover this issue during development and testing. It was a surprise to them.

What boggles my mind is that they chose to rebuild the engine instead of recommending impacted cars simply switch to 5w30 oil. Doing so would jeopardize their PZEV certification.

 

My car will see ~3500 miles/year so the oil will be changed by the Jaguar dealer at the annuals. After that, I will do the oil changes if I still have the car after 5 years.

 

How can you say this? You don't even know how the OEM tests?

You're right... because there's nothing wrong with the oil and it "lasts" forever since oil doesn't wear out. However, additive packages improved, filtration methods and technology improved, and oil capacity has increased... this leads to cleaner oil combined with sufficient additives to clean/protect the engine, and thus allowing for an increased oil change interval. But of course we would have to test the oil after X amount of miles to determine if it was within acceptable levels, and we don't know how to do that...



Yes, way to not quit!!! Way to ask Subaru to fix something that there's a class action lawsuit out there which forces them to fix!

That and 5w30 oil wouldn't actually fix the problem since the oil molecules are still the same size. Switching to conventional might help though, but that it wouldn't eliminate the problem since the issue was relatively significant.

 

Well, based on fact (oil analysis) rather than anecdote and supposition, the oil we are using is still quite good after 3750 miles and 6250 miles. Sometime early next year I will know if the oil is perfectly safe to 10k miles or is starting to get long in the tooth. I don't believe gunkification is dependent on the age of the oil. I believe the deposits build up as quickly when the oil is new as it does when it is old. At temp, new oil will coke up just as quickly as old oil, unless the additive component preventing buildup has been depleted.

 

It may be a characteristic of current DI engine designs .. I doubt that it was an intended or anticipated characteristic.

Perhaps for you. I strongly doubt that everyone wants the intake off
every 30k for some perceived minor benefit.

Doubly so if a supercharger removal is required before even getting at
the intake.

 

Not in my book. I'm a hardcore code toad and proud of it.

 

Like I said 1 in X units before warranty end.

You may test to 150k miles and find the failures.

But, the failures will be at a rate of 1 in Z units to 150k,
and 1 in X units before warranty end.

At that point, with the data in hand, upper management in the sales and financial
side will make a decision. Engineers seldom get a say in sales and financial matters.

As to the the nature of failure rates, it is based on statistical
probabilities.

I have yet to hear of a single mainstream automobile manufacturer
that can or will state publicly that all, that is,
every single engine without exception
will not fail before 150k miles.

So, you can test to 150k miles, and address the failures found
in that 150k miles, but you cannot assert that every engine will
last 150k miles.

Or, are you now asserting that your employer can and will state
that every single engine will last 150k miles? I didn't think so.

I have, and am well aware of how the financials work.

 

I'm a little late to the conversation but I had my first oil change done at 8000 miles and from here on out will have it done every 10k miles or 1 year. Whichever comes first.