Major engine Failures - one year overview
 

Owning this car for almost a year now and belonging to this fantastic forum the posts that catch my attention the most are the major engine failures. Now of course this happens with all new cars, especially new engine designs so I'm not chicken little, just looking at the reports from an objective perspective.

The interesting thing is we all thought the ultra-high compression ratio would point to the short-block being the weak link, remember when nay-sayers were claiming FI would be impossible without swaping pistons?

Well FB proved that not to be the case, the short-block surviving amazing boost and torque levels. At the time we all thought these were bullet proof engines with full blown's work, really looks like Subaru did their homework with the short-block.

But now we are still seeing folks with blown-up engines and not just FI guys, many reported completely stock. The common theme are the cylinder heads. We've had broken camshafts, broken rocker arms, burnt coilpacks from hot cylinder heads, and of course the blown DI O-rings leading to catastrophic failure. Not saying the heads are the root cause but all these issue's are cylinder head localized.

Its not too surprising considering this is the first NA H-4 Subaru boxer with a 7400 redline and 100hp/L, all that performance is made possible from the head design/geometry/DI integration. Does Toyota, Subaru, or Yamaha manufacture the cylinder heads, did they push too far?

I know a lot of us bought these cars for Toyota/Scion reliability, Subaru boxer reliability was rock solid till the late 90's, back then a Subaru engine was good for an easy 300k miles. And lets face it most any Toyota engine made will last that long if it is maintained. It will be interesting to see how these FA20 engines hold up the next few years.


Are these failures just a isolated cases or will these issues prove to be a long term issue affecting more and more owners the longer they own their cars? I firmly believe the long term success for this car absolutely depends on engine durability as the Toyota reputation is a big reason for the huge sales.

I have to stop you here. You can't expect every single motor to be perfect. That's what failure rates are. How many cars are on the road now? How many have blown engines?

The thing about forums like this is that every little thing gets brought to attention. Then all of a sudden, everyone starts saying, "I have that noise too."

Many of these cases are related to improper FI builds (which is something that no motor can with stand) and cars that see the track every weekend. Yes the motor should be able to withstand tracking, but that doesn't it can't fail. A good example would be the cars that are running in the 24hr races. Try that with even the most reliable motors.

Did you read all of OP's post? he basically touched on everything you did.

The only common aspect of our two posts are the FI parts.

Humnm

Yea I said I'm not playing chicken little, the problems aren't widespread. But its important to study up, because the more we learn about these engines from completely stock to full blown the sooner we learn the quirks and can take counter measures to ensure a long engine life.

Look at any good any car forum and there is usually a long thread about a problem that goes on for a while then someone figures out a fix. Raising awareness is the first step, not burying your head in the sand and thinking the OEM will solve all problems. It rarely works out that way.

My favorite example is Spyderchat. The last Toyota sports car (MR2 Spyder) had an issue where the cats on the header crumbled and the ceramic got sucked into the cylinders, quite a few blown motors. Toyota never really acknowledged the problem, but on that forum there is an FAQ that says the first thing you do when buying an MR-S is a compression check then degut those cats. Simple solution to a big problem.

That is what forums like this can be good for.

Ya sorry, I was kind of ranting at the mass hysteria type thing more than anything else. I completely agree with you though.

No mass hysteria at all, heck my FR-S is running like a top and I couldn't be happier with it. But I want us all to learn from folks with blown motors so we can prevent it.

I remember the 2005 turbo forester, around 30-70k miles quite a few folks were blowing up their engines. All sorts of theories, everyone thought it was the turbo blades breaking apart and ending up seizing the pistons, many right after the warranty was up. Turned out that the folks who removed the cat before the turbo never had a problem (it was the cat destroying the turbo, then the turbo destroying the engine.) Figuring out stuff like that early will only benefit all of us. DI is a new challenge for many of us, but I am sure as a group it can be solved.

I know the FA motors are a lot different than the EJ ones, but a very common failure on the EJ motors is the AVCS system. There are small screens inside the banjo bolts for the oil lines, meant to be in line filters. On the EJ's the screens can get clogged or rip out and get sucked into the AVCS system which can cause valve overlap or at the very least very rough running. I haven't taken apart any FA20's yet, but odds are the banjo bolt screen system is still there. Removing the screens would be my first move on any Subaru motor.
If anyone has the time and tools to do it, I encourage you to check to see if there are screens in there and report back. Also if anyone is taking off their oil pan, be sure to inspect the oil pickup tube.

If one is to look for a good statistical analysis of the situation, the forum is not a good place for that... any forum. Problem is, people with NO issues don't just post up every day and report that they have no issues. By the very nature of a forum, only people with issues are posting, looking for a solution/suggestions/comments. I bet the actual stats of blow motor is very low world wide. Throwing out the FI blown motor, how many truly stock motors are blow that wasn't a cause of the driving situation (over rev, low oil, etc)? It is hard to say judging purely on what is said via the internet.

Completely agree. Most people seek out these types of forums when in search of solutions to some kind of problem.

Also on this forum I've noticed the vast majority of threads pertaining to failed motors or the DI failure are all started by the same few people. I'm not implying that these folks are not knowledgeable, as they seem to be far more knowledgeable than most, myself included. Almost everyone else aside from the OP of these threads is just speculating or being a car hypochondriac.

I feel like the common denominators are FI or heavy tracking, which immediately cuts the potentially affected group to a very small number. Then within this group, few motors have outright failed. Just seems like if it were a actual manufacturing flaw it would be happening much more often to bone stock daily drivers and people who never track the car.

I think the DI problem is going to be a "forum fix" for sure on the early model 86's. It'll be one of those things that we will post in our "For Sale" threads in a year or so. "The car has been tuned to prevent detonation" and something we ask about when buying a first year 86. "Has it been tuned?" Great thread. Crossing my fingers that the conspiracy theorists don't ruin it. I plan to keep this car for a LONG time as a DD and potentially a track car in the future (cheap car, great balance, and I won't be out a TON of money if I wreck it), so thread is a great one for me.

I agree with you, and from what I can tell so does the OP. I think this thread is more information searching. Even with the forums going crazy over some failures, they are still few and far between thankfully....even here. That is good news in my eyes. :happy0180:

I still have no clue, when is the "detonation" said to happen? What situation causes the engine knock?

With modern manufacturing, and practices such as six sigma, you can expect very little variation between engines and very few failures due to manufacturing defects. In a plant run according to the best practices (many of which Toyota pioneered) any more than a small handful of engine failures would therefore implicate design, not manufacturing errors.

that's because the first technical topic forum is issues, warranty, and recalls and has more visibility than the other threads. I don't like to associate with the issues topic threads often because it starts to make me believe that the car is problematic, when it's really fine but we are all focusing on isolated cases.

I'd say this is worth talking about. We have a frs at my work thats about to get its 4th rebuild. (under warranty) same problem the rockers are blowing through the valve cover. I have pictures and our tech guys are currently investigating it. Crazy to thing about the same car going through 4 rebuilds due to the SAME issue.... and the previous owner had returned the car and got a new one. When that car came back for a 5k service it was missing 3.6 quarts of oil....

Yet the majority have never had an issue. There is something very strange and most certainly not normal going on there.

Hey Tcoat, how you know if rockers go bad?

When I decelerate below 4th gear (downshifting), I hear a click click sound. Like PVC plastic on PVC plastic. This is under 3/4k rpms.


****PVC piping click***********

If you hear a slapping noise at idle. Or there's a hole in the engine. Or tear the engine apart and look for scarring in the head.

N1rve gets it.

Or if it just plain won't go anymore.
Every single little noise is not an indication your engine is bad.

Where did the oil go???

check PCV

burned it up. Felt really sorry for lady... :mad0259:

So you are trying to tell us that one engine has blown up 4 times for burning oil to the point it was low 3.6 quarts?

I just had my '13 towed to the Scion dealer with what I suspect is a catastrophic engine failure. I will know more when the tech gets to look at it on Monday. The car is an early production '13 that we picked up in July '12 and has just under 40k miles on it.

I heard a nasty crunching sound, check engine light came on. The just about every other light came on. Engine stalled. I coasted it into a parking lot.

The engine won't start. The engine does turn with the ignition key turned to start (I thought the clutch / flywheel may have blown up) but it seems to spin without much resistance. There is no sign of engine internals becoming external and the engine oil level seems fine. With no gaping holes in the block and no real knocking when I crank it over with the key, I'm thinking this is going to be something in the heads.

I just wanted to get this directly to the dealer, so I didn't check the codes before it went.

I also have a Subaru Outback that I need to change the timing belt, clutch and headgaskets on before winter. I was going to pull the motor this morning. I'm glad I didn't because my wife and I would be sharing a Miata on summer tires.

-Justin

way to necro the dead ... but seriously there are a lot of .. research and development in our engine motors or quality control .. at least in my opinion

As an outside observer this looks quite bad, for the owner or whoever is doing these "rebuilds". Four engine rebuilds when no one else has this issue anymore as well as missing oil? Give this owner a new long block, valvetrain, ecu and let's see if it happens again instead of a top end "rebuild" that's 3 times too many for an engine, especially with the newer ones lasting longer, something doesn't sound right.

Sorry to hear...keep us updated!

Just got a call from the service advisor. Apparently the engine is seized up and won't turn over. This wasn't the case yesterday, as I had my wife turn the key and I watched the accessory drive belts turning. I'm not sure how it went from spinning too freely to not spinning at all while sitting.... but I still have no idea exactly what is broken.

Apparently the code thrown by the ECU was simply 'internal engine failure'. At least I wasn't just assuming the worst, I was actually experiencing the worst. I mean, my engine's dead but at least I'm not a pessimist.

-Justin

Probably cooled down and all the clearances tightened up to zilch.

hope they do not try to find a reason to blame you as they usually do. Did you get all oil changes at the dealer??

I got the first one at the dealer. Sat in the waiting room for almost 4 hours for a stupid oil change with an appointment. Unless that waiting room added complementary hookers, there was no way I was wasting another saturday there.

I did keep records of all my oil changes. All were around 5k miles with one early one closer to 8k miles.

I never expected the original tires to outlast the original engine. I guess I should have switched to a winter engine for half the year like I did with the tires.

-Justin

That was my experience too with the oil changes. Have been doing them after the first one was done at the dealer. I have all the recipts too....even took pictures of the oil bottles and bought the filters at the dealer in good faith.


Let us known what happens. Good luck!

My understanding is that the clearances are larger in a cold engine.
Maybe they kept cranking it until it seized

Read all your posts on this page. My bet is a wrist pin tore out of a piston. That's the weak spot if the stock pistons. engine may turn over, until some part of a rod or piston jams against something, then it will be seized. Have they tried turning the engine backwards by hand with a breaker bar on the crank pulley?

The rod usually breaks after a piston failure and windows the block, but if it stayed mostly intact, it likely wouldn't punch a hole in the block.

On a related note, they are a dealer, they could simply be lying.

If that didn't happen, and a rocker ejected (which is very possible) and went out the bottom of the valve cover, it's possible you wouldn't see a hole and there wouldn't be a huge amount of oil leaked out. Seizure could be due to bits of a broken valve jamming against a piston... Assuming the ejecting rocker blew out a valve spring retainer.

Speculation is irrelevant. Just humoring myself. Either way, there's no way your motor doesn't need a total rebuild.

I've been out of town for a few days and hadn't heard anything. I sent an email to the service advisor before I got on my plane home and had a response when I landed.

His email just said that they ordered a new short block and heads.

I didn't get the response until after business hours so I couldn't get clarification, but I assume they would have to give me an estimate and get my approval to proceed if this wasn't being covered under warranty.

I think the service advisor may be avoiding me because he thinks I'll be upset that it's going to take a while. He's not realizing that I'll be pretty pleased that this isn't coming out of my pocket (assuming that's the case).

I'll try to confirm the warranty status and see if I can get more information on the failure itself.

-Justin

Small update - block and heads are expected to arrive at the dealer on Wednesday, then they will get to assembling and installing.

-Justin

Who is paying for the work? Because if they charge you shop rates... be prepared to be torn a new one.

I was never presented with an estimate / quote and never signed any authorization to perform any specific work. Since they went ahead and ordered the parts without my authorization, I am assuming the work is under warranty.

Also, the service advisor had asked me for service records (which I provided) because he knew Toyota would be asking for them.

I sent an email asking for a loaner car (I usually work from home and we have three cars, so having this one down isn't that big a deal) since I will need to make some visits next week so I need a car that I can answer a phone call in while I'm driving. I only drive the Miata with the top down, so the noise makes that impossible. Also, the temperatures are going to make top-down driving a bit uncomfortable real soon.

I almost feel guilty on the warranty stuff. I'll have this engine replacement which I am assuming would run ~$10k and I had just dropped the car off with them before the regular warranty ran out to address a bunch of issues that all had TSBs (water in tail lights, window seals not sealing properly, cricket noise from high pressure fuel pump - the fix actually made this one worse, and an ignition coil that was throwing a code). That work totaled just around $4k.

-Justin